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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 = 'ar' 
  AND gp.group_id IN (57, 54, 51, 48, 47)

Query time 0.00062

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "17.51"
    },
    "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": 5,
          "rows_produced_per_join": 5,
          "filtered": "100.00",
          "index_condition": "(`betaatif_store`.`gpf`.`group_id` in (57,54,51,48,47))",
          "cost_info": {
            "read_cost": "3.01",
            "eval_cost": "0.50",
            "prefix_cost": "3.51",
            "data_read_per_join": "520"
          },
          "used_columns": [
            "feature_id",
            "group_id"
          ]
        }
      },
      {
        "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": [
            "betaatif_store.gpf.group_id"
          ],
          "rows_examined_per_scan": 4,
          "rows_produced_per_join": 20,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "5.00",
            "eval_cost": "2.00",
            "prefix_cost": "10.51",
            "data_read_per_join": "320"
          },
          "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": [
            "betaatif_store.gpf.feature_id",
            "betaatif_store.gp.product_id",
            "const"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 20,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "5.00",
            "eval_cost": "2.00",
            "prefix_cost": "17.51",
            "data_read_per_join": "15K"
          },
          "used_columns": [
            "feature_id",
            "product_id",
            "variant_id",
            "lang_code"
          ]
        }
      }
    ]
  }
}

Result

feature_id	product_id	variant_id	group_id
2	556	6	47
2	557	7	47
2	558	9	47
2	559	11	47
2	560	6	48
2	561	7	48
2	562	9	48
2	563	11	48
2	572	6	51
2	573	7	51
2	574	9	51
2	575	11	51
2	584	6	54
2	585	7	54
2	586	9	54
2	587	12	54
2	596	6	57
2	597	7	57
2	598	9	57
2	599	12	57

feature_id	product_id	variant_id	group_id
2	556	6	47
2	557	7	47
2	558	9	47
2	559	11	47
2	560	6	48
2	561	7	48
2	562	9	48
2	563	11	48
2	572	6	51
2	573	7	51
2	574	9	51
2	575	11	51
2	584	6	54
2	585	7	54
2	586	9	54
2	587	12	54
2	596	6	57
2	597	7	57
2	598	9	57
2	599	12	57

feature_id	product_id	variant_id	group_id
2	556	6	47
2	557	7	47
2	558	9	47
2	559	11	47
2	560	6	48
2	561	7	48
2	562	9	48
2	563	11	48
2	572	6	51
2	573	7	51
2	574	9	51
2	575	11	51
2	584	6	54
2	585	7	54
2	586	9	54
2	587	12	54
2	596	6	57
2	597	7	57
2	598	9	57
2	599	12	57

feature_id	product_id	variant_id	group_id
2	556	6	47
2	557	7	47
2	558	9	47
2	559	11	47
2	560	6	48
2	561	7	48
2	562	9	48
2	563	11	48
2	572	6	51
2	573	7	51
2	574	9	51
2	575	11	51
2	584	6	54
2	585	7	54
2	586	9	54
2	587	12	54
2	596	6	57
2	597	7	57
2	598	9	57
2	599	12	57