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 (
    96688, 96689, 96690, 96691, 96692, 96694, 
    96695, 96696, 96697, 96708, 96718, 
    96719, 96720, 96724, 96734, 96735, 
    96738, 96739, 96743, 96746, 96747, 
    96749, 96751, 96758, 96759, 96764, 
    96775, 96778, 96779, 96780, 96789, 
    96790, 96791, 96839, 96840, 96841, 
    96918, 96919, 96985, 96986, 96987, 
    96988, 96989, 96990, 96991, 96992, 
    96993, 96994, 96995, 96996, 96997, 
    96998, 96999, 97000, 97001, 97002, 
    97003, 97004, 97005, 97006, 97007, 
    97008, 97009, 97010, 97083, 97219, 
    97220, 97221, 97222, 97223, 97224, 
    97225, 97226, 97227, 97567, 97570, 
    97573, 97574, 97575, 97576, 97577, 
    97578, 97579, 97580, 97581, 97582, 
    97583, 97584, 97585, 97586, 97682, 
    97683, 97684, 97685, 97686, 97687
  )

Query time 0.00033

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1.05"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "f",
          "access_type": "ALL",
          "possible_keys": [
            "idx_group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.10",
            "prefix_cost": "0.35",
            "data_read_per_join": "104"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "g",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "id"
          ],
          "key_length": "3",
          "ref": [
            "nuie_scalesta_net.f.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.10",
            "prefix_cost": "0.70",
            "data_read_per_join": "400"
          },
          "used_columns": [
            "id",
            "code"
          ]
        }
      },
      {
        "table": {
          "table_name": "p",
          "access_type": "ref",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "ref": [
            "nuie_scalesta_net.f.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "index_condition": "(`nuie_scalesta_net`.`p`.`product_id` in (96688,96689,96690,96691,96692,96694,96695,96696,96697,96708,96718,96719,96720,96724,96734,96735,96738,96739,96743,96746,96747,96749,96751,96758,96759,96764,96775,96778,96779,96780,96789,96790,96791,96839,96840,96841,96918,96919,96985,96986,96987,96988,96989,96990,96991,96992,96993,96994,96995,96996,96997,96998,96999,97000,97001,97002,97003,97004,97005,97006,97007,97008,97009,97010,97083,97219,97220,97221,97222,97223,97224,97225,97226,97227,97567,97570,97573,97574,97575,97576,97577,97578,97579,97580,97581,97582,97583,97584,97585,97586,97682,97683,97684,97685,97686,97687))",
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.10",
            "prefix_cost": "1.05",
            "data_read_per_join": "16"
          },
          "used_columns": [
            "product_id",
            "parent_product_id",
            "group_id"
          ]
        }
      }
    ]
  }
}