SELECT 
  SQL_CALC_FOUND_ROWS (
    CASE WHEN products.parent_product_id <> 0 THEN products.parent_product_id ELSE products.product_id END
  ) AS product_id, 
  IF(
    shared_descr.product_id IS NOT NULL, 
    shared_descr.product, descr1.product
  ) as product, 
  companies.company as company_name, 
  GROUP_CONCAT(
    products.product_id 
    ORDER BY 
      products.parent_product_id ASC, 
      products.product_id ASC
  ) AS product_ids, 
  GROUP_CONCAT(
    products.product_type 
    ORDER BY 
      products.parent_product_id ASC, 
      products.product_id ASC
  ) AS product_types, 
  GROUP_CONCAT(
    products.parent_product_id 
    ORDER BY 
      products.parent_product_id ASC, 
      products.product_id ASC
  ) AS parent_product_ids, 
  products.product_type, 
  products.parent_product_id 
FROM 
  cscart_products as products 
  LEFT JOIN cscart_product_features_values as var_val_18 ON var_val_18.product_id = products.product_id 
  AND var_val_18.lang_code = 'en' 
  AND var_val_18.feature_id = 18 
  LEFT JOIN cscart_product_descriptions as descr1 ON descr1.product_id = products.product_id 
  AND descr1.lang_code = 'en' 
  LEFT JOIN cscart_product_prices as prices ON prices.product_id = products.product_id 
  AND prices.lower_limit = 1 
  LEFT JOIN cscart_companies AS companies ON companies.company_id = products.company_id 
  INNER JOIN cscart_products_categories as products_categories ON products_categories.product_id = products.product_id 
  INNER JOIN cscart_categories ON cscart_categories.category_id = products_categories.category_id 
  AND (
    cscart_categories.usergroup_ids = '' 
    OR FIND_IN_SET(
      0, cscart_categories.usergroup_ids
    ) 
    OR FIND_IN_SET(
      1, cscart_categories.usergroup_ids
    )
  ) 
  AND cscart_categories.status IN ('A', 'H') 
  AND cscart_categories.storefront_id IN (0, 1) 
  LEFT JOIN cscart_ult_product_descriptions shared_descr ON shared_descr.product_id = products.product_id 
  AND shared_descr.company_id = 1 
  AND shared_descr.lang_code = 'en' 
WHERE 
  1 
  AND (
    var_val_18.variant_id IN (1288)
  ) 
  AND cscart_categories.category_id IN (306) 
  AND companies.status IN ('A') 
  AND (
    products.usergroup_ids = '' 
    OR FIND_IN_SET(0, products.usergroup_ids) 
    OR FIND_IN_SET(1, products.usergroup_ids)
  ) 
  AND products.status IN ('A') 
  AND prices.usergroup_id IN (0, 0, 1) 
GROUP BY 
  product_id 
ORDER BY 
  product asc, 
  products.product_id ASC 
LIMIT 
  0, 12

Query time 0.01170

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "143.59"
    },
    "ordering_operation": {
      "using_filesort": true,
      "grouping_operation": {
        "using_temporary_table": true,
        "using_filesort": true,
        "buffer_result": {
          "using_temporary_table": true,
          "nested_loop": [
            {
              "table": {
                "table_name": "cscart_categories",
                "access_type": "const",
                "possible_keys": [
                  "PRIMARY",
                  "c_status",
                  "p_category_id"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "category_id"
                ],
                "key_length": "3",
                "ref": [
                  "const"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 1,
                "filtered": "100.00",
                "cost_info": {
                  "read_cost": "0.00",
                  "eval_cost": "0.10",
                  "prefix_cost": "0.00",
                  "data_read_per_join": "4K"
                },
                "used_columns": [
                  "category_id",
                  "storefront_id",
                  "usergroup_ids",
                  "status"
                ]
              }
            },
            {
              "table": {
                "table_name": "companies",
                "access_type": "ALL",
                "possible_keys": [
                  "PRIMARY"
                ],
                "rows_examined_per_scan": 2,
                "rows_produced_per_join": 1,
                "filtered": "50.00",
                "cost_info": {
                  "read_cost": "0.62",
                  "eval_cost": "0.10",
                  "prefix_cost": "0.72",
                  "data_read_per_join": "5K"
                },
                "used_columns": [
                  "company_id",
                  "status",
                  "company"
                ],
                "attached_condition": "(`test2_gaseus`.`companies`.`status` = 'A')"
              }
            },
            {
              "table": {
                "table_name": "products_categories",
                "access_type": "ref",
                "possible_keys": [
                  "PRIMARY",
                  "pt"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "category_id"
                ],
                "key_length": "3",
                "ref": [
                  "const"
                ],
                "rows_examined_per_scan": 154,
                "rows_produced_per_join": 154,
                "filtered": "100.00",
                "using_index": true,
                "cost_info": {
                  "read_cost": "1.21",
                  "eval_cost": "15.40",
                  "prefix_cost": "17.33",
                  "data_read_per_join": "2K"
                },
                "used_columns": [
                  "product_id",
                  "category_id"
                ]
              }
            },
            {
              "table": {
                "table_name": "var_val_18",
                "access_type": "eq_ref",
                "possible_keys": [
                  "PRIMARY",
                  "fl",
                  "variant_id",
                  "lang_code",
                  "product_id",
                  "fpl",
                  "idx_product_feature_variant_id"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "feature_id",
                  "product_id",
                  "variant_id",
                  "lang_code"
                ],
                "key_length": "15",
                "ref": [
                  "const",
                  "test2_gaseus.products_categories.product_id",
                  "const",
                  "const"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 154,
                "filtered": "100.00",
                "using_index": true,
                "cost_info": {
                  "read_cost": "38.50",
                  "eval_cost": "15.40",
                  "prefix_cost": "71.23",
                  "data_read_per_join": "119K"
                },
                "used_columns": [
                  "feature_id",
                  "product_id",
                  "variant_id",
                  "lang_code"
                ]
              }
            },
            {
              "table": {
                "table_name": "products",
                "access_type": "eq_ref",
                "possible_keys": [
                  "PRIMARY",
                  "status"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "product_id"
                ],
                "key_length": "3",
                "ref": [
                  "test2_gaseus.products_categories.product_id"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 15,
                "filtered": "9.95",
                "cost_info": {
                  "read_cost": "38.50",
                  "eval_cost": "1.53",
                  "prefix_cost": "125.13",
                  "data_read_per_join": "100K"
                },
                "used_columns": [
                  "product_id",
                  "product_type",
                  "status",
                  "company_id",
                  "usergroup_ids",
                  "parent_product_id"
                ],
                "attached_condition": "((`test2_gaseus`.`products`.`company_id` = `test2_gaseus`.`companies`.`company_id`) and ((`test2_gaseus`.`products`.`usergroup_ids` = '') or (0 <> find_in_set(0,`test2_gaseus`.`products`.`usergroup_ids`)) or (0 <> find_in_set(1,`test2_gaseus`.`products`.`usergroup_ids`))) and (`test2_gaseus`.`products`.`status` = 'A'))"
              }
            },
            {
              "table": {
                "table_name": "prices",
                "access_type": "ref",
                "possible_keys": [
                  "usergroup",
                  "product_id",
                  "lower_limit",
                  "usergroup_id"
                ],
                "key": "product_id",
                "used_key_parts": [
                  "product_id"
                ],
                "key_length": "3",
                "ref": [
                  "test2_gaseus.products_categories.product_id"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 15,
                "filtered": "99.91",
                "cost_info": {
                  "read_cost": "3.83",
                  "eval_cost": "1.53",
                  "prefix_cost": "130.50",
                  "data_read_per_join": "367"
                },
                "used_columns": [
                  "product_id",
                  "lower_limit",
                  "usergroup_id"
                ],
                "attached_condition": "((`test2_gaseus`.`prices`.`lower_limit` = 1) and (`test2_gaseus`.`prices`.`usergroup_id` in (0,0,1)))"
              }
            },
            {
              "table": {
                "table_name": "shared_descr",
                "access_type": "eq_ref",
                "possible_keys": [
                  "PRIMARY",
                  "product_id",
                  "company_id"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "product_id",
                  "lang_code",
                  "company_id"
                ],
                "key_length": "13",
                "ref": [
                  "test2_gaseus.products_categories.product_id",
                  "const",
                  "const"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 15,
                "filtered": "100.00",
                "cost_info": {
                  "read_cost": "3.83",
                  "eval_cost": "1.53",
                  "prefix_cost": "135.86",
                  "data_read_per_join": "58K"
                },
                "used_columns": [
                  "product_id",
                  "lang_code",
                  "company_id",
                  "product"
                ]
              }
            },
            {
              "table": {
                "table_name": "descr1",
                "access_type": "eq_ref",
                "possible_keys": [
                  "PRIMARY",
                  "product_id"
                ],
                "key": "PRIMARY",
                "used_key_parts": [
                  "product_id",
                  "lang_code"
                ],
                "key_length": "9",
                "ref": [
                  "test2_gaseus.products_categories.product_id",
                  "const"
                ],
                "rows_examined_per_scan": 1,
                "rows_produced_per_join": 15,
                "filtered": "100.00",
                "cost_info": {
                  "read_cost": "6.20",
                  "eval_cost": "1.53",
                  "prefix_cost": "143.59",
                  "data_read_per_join": "69K"
                },
                "used_columns": [
                  "product_id",
                  "lang_code",
                  "product"
                ]
              }
            }
          ]
        }
      }
    }
  }
}

Result

product_id product company_name product_ids product_types parent_product_ids product_type parent_product_id
12349 Cylinder pressure regulator Omega Gaseus 12349,12350,12351,12352,12353,12354,12355,12356,12357,12358,12359,12360,12361,12362,12363 P,V,V,V,V,V,V,V,V,V,V,V,V,V,V 0,12349,12349,12349,12349,12349,12349,12349,12349,12349,12349,12349,12349,12349,12349 P 0
12364 Cylinder pressure regulator Omega II Gaseus 12364,12365,12366,12367,12368,12369,12370,12371,12372,12373,12374,12375,12376,12377,12378 P,V,V,V,V,V,V,V,V,V,V,V,V,V,V 0,12364,12364,12364,12364,12364,12364,12364,12364,12364,12364,12364,12364,12364,12364 P 0
12259 Cylinder pressure regulator Sigma Gaseus 12259,12260,12261,12262,12263,12264,12265,12266,12267,12268,12269,12270,12271,12272,12273,12274,12275,12276,12277,12278,12279,12280,12281,12282,12283,12284,12285,12286,12287,12288,12289,12290,12291,12292,12293,12294,12295,12296,12297,12298,12299,12300,12301,12302,12303,12304,12305,12306,12307,12308,12309,12310,12311,12312,12313,12314,12315,12316,12317,12318,12319,12320,12321,12322,12323,12324,12325,12326,12327,12328,12329,12330,12331,12332,12333,12334,12335,12336,12337,12338,12339,12340,12341,12342,12343,12344,12345,12346,12347,12348 P,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V 0,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259,12259 P 0
12504 Cylinder pressure regulator Thanos Gaseus 12504,12505,12506,12507,12508,12509,12510,12511,12512,12513,12514,12515,12516,12517,12518,12519,12520,12521,12522,12523 P,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V,V 0,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504,12504 P 0
12524 Cylinder pressure regulator Thanos II Gaseus 12524,12525,12526,12527,12528,12529,12530,12531,12532,12533,12534,12535 P,V,V,V,V,V,V,V,V,V,V,V 0,12524,12524,12524,12524,12524,12524,12524,12524,12524,12524,12524 P 0