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 (
    402092, 403976, 408452, 428407, 451396, 
    417863, 404877, 460518, 418662, 425706, 
    403670, 447102, 447465, 418224, 454664, 
    413860, 446202, 446424, 416636, 436995, 
    424216, 416027, 453105, 414898, 420267, 
    412406, 425747, 441765, 406851, 447289, 
    403492, 409045, 411798, 455469, 403314, 
    459175, 412726, 446945, 419788, 441409, 
    421788, 429875, 408990, 457492, 402535, 
    424481, 421915, 427033
  )

Query time 0.00043

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost": 0.03140489,
    "nested_loop": [
      {
        "table": {
          "table_name": "g",
          "access_type": "index",
          "possible_keys": ["PRIMARY"],
          "key": "idx_group_code",
          "key_length": "387",
          "used_key_parts": ["code"],
          "loops": 1,
          "rows": 2,
          "cost": 0.00693929,
          "filtered": 100,
          "using_index": true
        }
      },
      {
        "table": {
          "table_name": "f",
          "access_type": "ref",
          "possible_keys": ["idx_group_id"],
          "key": "idx_group_id",
          "key_length": "3",
          "used_key_parts": ["group_id"],
          "ref": ["u985510652_ecartify.g.id"],
          "loops": 2,
          "rows": 1,
          "cost": 0.00527872,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "p",
          "access_type": "ref",
          "possible_keys": ["PRIMARY", "idx_group_id"],
          "key": "idx_group_id",
          "key_length": "3",
          "used_key_parts": ["group_id"],
          "ref": ["u985510652_ecartify.g.id"],
          "loops": 2,
          "rows": 8,
          "cost": 0.01918688,
          "filtered": 100,
          "index_condition": "p.product_id in (402092,403976,408452,428407,451396,417863,404877,460518,418662,425706,403670,447102,447465,418224,454664,413860,446202,446424,416636,436995,424216,416027,453105,414898,420267,412406,425747,441765,406851,447289,403492,409045,411798,455469,403314,459175,412726,446945,419788,441409,421788,429875,408990,457492,402535,424481,421915,427033)"
        }
      }
    ]
  }
}