SELECT 
  pf.feature_id, 
  pf.company_id, 
  pf.feature_type, 
  pf.parent_id, 
  pf.display_on_product, 
  pf.display_on_catalog, 
  pf.display_on_header, 
  pf.categories_path, 
  pf.status, 
  pf.comparison, 
  pf.position, 
  pf.purpose, 
  pf.feature_style, 
  pf.filter_style, 
  pf.feature_code, 
  pfd.description, 
  pfd.lang_code, 
  pfd.prefix, 
  pfd.suffix, 
  pfd.full_description, 
  pfv.value, 
  pfv.variant_id, 
  pfv.value_int, 
  pfv.product_id 
FROM 
  cscart_product_features_values AS pfv 
  LEFT JOIN cscart_product_features AS pf ON pfv.feature_id = pf.feature_id 
  LEFT JOIN cscart_product_features_descriptions AS pfd ON pfd.feature_id = pf.feature_id 
  AND pfd.lang_code = 'en' 
WHERE 
  1 = 1 
  AND pfv.product_id IN (
    12483, 12484, 12485, 12486, 12487, 12488, 
    12489, 12490, 12491, 12482, 12481, 
    12480, 12479, 12478, 12477, 12476, 
    12475, 12474, 12473, 12472, 12471, 
    12470, 12469, 12468, 12467, 12466, 
    12465, 12464, 12493, 12492
  ) 
  AND pfv.lang_code = 'en' 
  AND pf.feature_code IN ('Brand', 'ISBN', 'GTIN', 'MPN')

Query time 0.00578

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "998.23"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "pfv",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "lang_code",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "idx_product_feature_variant_id",
          "used_key_parts": [
            "product_id"
          ],
          "key_length": "3",
          "rows_examined_per_scan": 1382,
          "rows_produced_per_join": 752,
          "filtered": "54.46",
          "index_condition": "((`test2_gaseus`.`pfv`.`product_id` in (12483,12484,12485,12486,12487,12488,12489,12490,12491,12482,12481,12480,12479,12478,12477,12476,12475,12474,12473,12472,12471,12470,12469,12468,12467,12466,12465,12464,12493,12492)) and (`test2_gaseus`.`pfv`.`lang_code` = 'en'))",
          "cost_info": {
            "read_cost": "554.14",
            "eval_cost": "75.27",
            "prefix_cost": "629.41",
            "data_read_per_join": "582K"
          },
          "used_columns": [
            "feature_id",
            "product_id",
            "variant_id",
            "value",
            "value_int",
            "lang_code"
          ]
        }
      },
      {
        "table": {
          "table_name": "pf",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "feature_id"
          ],
          "key_length": "3",
          "ref": [
            "test2_gaseus.pfv.feature_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 301,
          "filtered": "40.00",
          "cost_info": {
            "read_cost": "188.18",
            "eval_cost": "30.11",
            "prefix_cost": "892.86",
            "data_read_per_join": "355K"
          },
          "used_columns": [
            "feature_id",
            "feature_code",
            "company_id",
            "purpose",
            "feature_style",
            "filter_style",
            "feature_type",
            "categories_path",
            "parent_id",
            "display_on_product",
            "display_on_catalog",
            "display_on_header",
            "status",
            "position",
            "comparison"
          ],
          "attached_condition": "(`test2_gaseus`.`pf`.`feature_code` in ('Brand','ISBN','GTIN','MPN'))"
        }
      },
      {
        "table": {
          "table_name": "pfd",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "feature_id",
            "lang_code"
          ],
          "key_length": "9",
          "ref": [
            "test2_gaseus.pfv.feature_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 301,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "75.27",
            "eval_cost": "30.11",
            "prefix_cost": "998.23",
            "data_read_per_join": "715K"
          },
          "used_columns": [
            "feature_id",
            "description",
            "full_description",
            "prefix",
            "suffix",
            "lang_code"
          ]
        }
      }
    ]
  }
}