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 (
    8322, 8324, 8323, 8325, 8326, 8327, 8328, 
    8329, 8332, 8645, 7546, 7547, 7548, 
    7545, 7665, 7556, 7667, 7661, 7508, 
    7929, 9730, 7925, 7928, 7927, 8065, 
    7926, 7930, 8647, 8635, 8637, 8638, 
    8641, 8636, 8639
  )

Query time 0.00056

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "47.61"
    },
    "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": 34,
          "rows_produced_per_join": 34,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`p`.`product_id` in (8322,8324,8323,8325,8326,8327,8328,8329,8332,8645,7546,7547,7548,7545,7665,7556,7667,7661,7508,7929,9730,7925,7928,7927,8065,7926,7930,8647,8635,8637,8638,8641,8636,8639))",
          "cost_info": {
            "read_cost": "20.41",
            "eval_cost": "3.40",
            "prefix_cost": "23.81",
            "data_read_per_join": "544"
          },
          "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": [
            "softwarepirmam_hewadelivard_cscart_4.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 34,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "8.50",
            "eval_cost": "3.40",
            "prefix_cost": "35.71",
            "data_read_per_join": "13K"
          },
          "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": [
            "softwarepirmam_hewadelivard_cscart_4.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 34,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "8.50",
            "eval_cost": "3.40",
            "prefix_cost": "47.61",
            "data_read_per_join": "3K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}