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 (
    312881, 312873, 312841, 312842, 312847, 
    312848, 312840, 312846, 312838, 312839, 
    312854, 312876, 312843, 312845, 312837, 
    312855, 312834, 312864, 312852, 312853, 
    312851, 312866, 312844, 312867, 312862, 
    312833, 312835, 312856, 312857, 312859, 
    312860, 312861, 312872, 312869, 312858, 
    312863, 312879, 312875, 312878, 312836, 
    312880, 312865, 312874, 312868, 312849, 
    312850, 312877
  )

Query time 0.00033

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 (312881,312873,312841,312842,312847,312848,312840,312846,312838,312839,312854,312876,312843,312845,312837,312855,312834,312864,312852,312853,312851,312866,312844,312867,312862,312833,312835,312856,312857,312859,312860,312861,312872,312869,312858,312863,312879,312875,312878,312836,312880,312865,312874,312868,312849,312850,312877)"
        }
      }
    ]
  }
}