SELECT 
  f.feature_id, 
  f.purpose, 
  p.product_id, 
  p.parent_product_id, 
  g.id, 
  g.code 
FROM 
  cscart_product_variation_group_features AS f 
  INNER JOIN cscart_product_variation_groups AS g ON f.group_id = g.id 
  INNER JOIN cscart_product_variation_group_products AS p ON f.group_id = p.group_id 
WHERE 
  p.product_id IN (
    12037, 12102, 12116, 12118, 12132, 12146, 
    12160, 12174, 12188, 12202, 8203, 8214, 
    8215, 8216, 8217, 8218, 8205, 8206, 
    8207, 8208, 8209, 8210, 8211, 8212, 
    1154, 3315, 6843, 3318, 3687, 5076, 
    6840, 4691, 3071, 513, 3505, 3319, 3306, 
    3296, 6841, 6846, 1172, 1173, 4917, 
    4918, 6962, 6966, 6967, 6965
  )

Query time 0.00102

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "104.51"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "p",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "product_id"
          ],
          "key_length": "3",
          "rows_examined_per_scan": 50,
          "rows_produced_per_join": 50,
          "filtered": "100.00",
          "index_condition": "(`gaseus`.`p`.`product_id` in (12037,12102,12116,12118,12132,12146,12160,12174,12188,12202,8203,8214,8215,8216,8217,8218,8205,8206,8207,8208,8209,8210,8211,8212,1154,3315,6843,3318,3687,5076,6840,4691,3071,513,3505,3319,3306,3296,6841,6846,1172,1173,4917,4918,6962,6966,6967,6965))",
          "cost_info": {
            "read_cost": "29.51",
            "eval_cost": "5.00",
            "prefix_cost": "34.51",
            "data_read_per_join": "800"
          },
          "used_columns": [
            "product_id",
            "parent_product_id",
            "group_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "g",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "id"
          ],
          "key_length": "3",
          "ref": [
            "gaseus.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 50,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "12.50",
            "eval_cost": "5.00",
            "prefix_cost": "52.01",
            "data_read_per_join": "19K"
          },
          "used_columns": [
            "id",
            "code"
          ]
        }
      },
      {
        "table": {
          "table_name": "f",
          "access_type": "ref",
          "possible_keys": [
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "ref": [
            "gaseus.p.group_id"
          ],
          "rows_examined_per_scan": 3,
          "rows_produced_per_join": 150,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "37.50",
            "eval_cost": "15.00",
            "prefix_cost": "104.51",
            "data_read_per_join": "15K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}