SELECT 
  pfv.feature_id, 
  pfv.product_id, 
  pfv.variant_id, 
  gp.group_id 
FROM 
  cscart_product_features_values AS pfv 
  INNER JOIN cscart_product_variation_group_products AS gp ON pfv.product_id = gp.product_id 
  INNER JOIN cscart_product_variation_group_features AS gpf ON gpf.group_id = gp.group_id 
  AND gpf.feature_id = pfv.feature_id 
WHERE 
  pfv.lang_code = 'en' 
  AND gp.group_id IN (
    9237, 9233, 7568, 9234, 9803, 9799, 9797, 
    10687, 9244, 9248, 9242, 9789, 9801, 
    10690, 10695, 7607, 7569, 7579, 7567, 
    9236, 9790, 10688, 9802, 9807, 7559, 
    10703, 9806, 9793, 9798, 10693, 7598, 
    9800, 9243, 10700, 9240, 7600, 9239, 
    7602, 10686, 9247, 10694, 9786, 9809, 
    9235, 9787, 9804, 7571, 9241, 10692, 
    9811, 9788, 7560, 9245, 10696, 9792, 
    7562, 9791, 9238, 9816, 9817, 8412, 
    9815, 8349, 8382
  )

Query time 0.00727

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1083.10"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "gpf",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "rows_examined_per_scan": 74,
          "rows_produced_per_join": 74,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "15.89",
            "eval_cost": "14.80",
            "prefix_cost": "30.69",
            "data_read_per_join": "7K"
          },
          "used_columns": [
            "feature_id",
            "group_id"
          ],
          "attached_condition": "(`webmarco`.`gpf`.`group_id` in (9237,9233,7568,9234,9803,9799,9797,10687,9244,9248,9242,9789,9801,10690,10695,7607,7569,7579,7567,9236,9790,10688,9802,9807,7559,10703,9806,9793,9798,10693,7598,9800,9243,10700,9240,7600,9239,7602,10686,9247,10694,9786,9809,9235,9787,9804,7571,9241,10692,9811,9788,7560,9245,10696,9792,7562,9791,9238,9816,9817,8412,9815,8349,8382))"
        }
      },
      {
        "table": {
          "table_name": "gp",
          "access_type": "ref",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "ref": [
            "webmarco.gpf.group_id"
          ],
          "rows_examined_per_scan": 9,
          "rows_produced_per_join": 698,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "74.69",
            "eval_cost": "139.67",
            "prefix_cost": "245.05",
            "data_read_per_join": "10K"
          },
          "used_columns": [
            "product_id",
            "group_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "pfv",
          "access_type": "ref",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "lang_code",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "fpl",
          "used_key_parts": [
            "feature_id",
            "product_id",
            "lang_code"
          ],
          "key_length": "12",
          "ref": [
            "webmarco.gpf.feature_id",
            "webmarco.gp.product_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 698,
          "filtered": "100.00",
          "using_index": true,
          "cost_info": {
            "read_cost": "698.37",
            "eval_cost": "139.67",
            "prefix_cost": "1083.10",
            "data_read_per_join": "540K"
          },
          "used_columns": [
            "feature_id",
            "product_id",
            "variant_id",
            "lang_code"
          ]
        }
      }
    ]
  }
}