SELECT 
  product_id, 
  feature_id, 
  variant_id 
FROM 
  cscart_product_features_values 
WHERE 
  product_id IN (
    12463, 12462, 12461, 12460, 12459, 12458, 
    12457, 12456, 12455, 12454, 12453, 
    12452, 12451, 12450, 12449, 12448, 
    12447, 12446, 12445, 12444, 12443, 
    12442, 12441, 12440, 12439, 12438, 
    12437, 12436, 12435, 12434, 12433, 
    12432, 12431, 12430, 12429, 12428, 
    12427, 12426, 12425, 12424
  ) 
  AND feature_id IN (625, 553, 624, 627, 628) 
  AND lang_code = 'en'

Query time 0.00548

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "7.83"
    },
    "table": {
      "table_name": "cscart_product_features_values",
      "access_type": "range",
      "possible_keys": [
        "PRIMARY",
        "fl",
        "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",
      "rows_examined_per_scan": 20,
      "rows_produced_per_join": 20,
      "filtered": "100.00",
      "using_index_for_skip_scan": true,
      "cost_info": {
        "read_cost": "5.84",
        "eval_cost": "2.00",
        "prefix_cost": "7.84",
        "data_read_per_join": "15K"
      },
      "used_columns": [
        "feature_id",
        "product_id",
        "variant_id",
        "lang_code"
      ],
      "attached_condition": "((`test2_gaseus`.`cscart_product_features_values`.`product_id` in (12463,12462,12461,12460,12459,12458,12457,12456,12455,12454,12453,12452,12451,12450,12449,12448,12447,12446,12445,12444,12443,12442,12441,12440,12439,12438,12437,12436,12435,12434,12433,12432,12431,12430,12429,12428,12427,12426,12425,12424)) and (`test2_gaseus`.`cscart_product_features_values`.`feature_id` in (625,553,624,627,628)) and (`test2_gaseus`.`cscart_product_features_values`.`lang_code` = 'en'))"
    }
  }
}