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 (
    10921, 10922, 10923, 10924, 10925, 10926, 
    10927, 10928, 10929, 10930, 10931, 
    10932, 10933, 10934, 10935, 10936, 
    10937, 10938, 10939, 10940, 10941, 
    10942, 10943, 10965, 10985, 11005, 
    11027, 11047, 11067, 11089, 11111, 
    11133, 11153, 11173, 11195, 11215, 
    11237, 11259, 11279, 11299, 11813, 
    11819, 11825, 11831, 11838, 11844, 
    11851, 11869
  )

Query time 0.00083

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "111.91"
    },
    "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": 54,
          "rows_produced_per_join": 54,
          "filtered": "100.00",
          "index_condition": "(`gaseus`.`p`.`product_id` in (10921,10922,10923,10924,10925,10926,10927,10928,10929,10930,10931,10932,10933,10934,10935,10936,10937,10938,10939,10940,10941,10942,10943,10965,10985,11005,11027,11047,11067,11089,11111,11133,11153,11173,11195,11215,11237,11259,11279,11299,11813,11819,11825,11831,11838,11844,11851,11869))",
          "cost_info": {
            "read_cost": "30.91",
            "eval_cost": "5.40",
            "prefix_cost": "36.31",
            "data_read_per_join": "864"
          },
          "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": 54,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "13.50",
            "eval_cost": "5.40",
            "prefix_cost": "55.21",
            "data_read_per_join": "21K"
          },
          "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": 162,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "40.50",
            "eval_cost": "16.20",
            "prefix_cost": "111.91",
            "data_read_per_join": "16K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}