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 (
    3884, 382, 3875, 2294, 112, 3471, 3880, 
    3877, 49265, 3859, 3879, 3881, 23162, 
    3860, 6089, 1781, 384, 3883, 385, 3882, 
    1755, 383, 4020, 1754, 4493, 41398, 
    52, 41399, 5581, 5577, 4500, 1059
  )

Query time 0.00137

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "p",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "idx_group_id"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["product_id"],
          "rows": 32,
          "filtered": 100,
          "index_condition": "p.product_id in (3884,382,3875,2294,112,3471,3880,3877,49265,3859,3879,3881,23162,3860,6089,1781,384,3883,385,3882,1755,383,4020,1754,4493,41398,52,41399,5581,5577,4500,1059)"
        }
      },
      {
        "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": ["dev_db.p.group_id"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "g",
          "access_type": "eq_ref",
          "possible_keys": ["PRIMARY"],
          "key": "PRIMARY",
          "key_length": "3",
          "used_key_parts": ["id"],
          "ref": ["dev_db.p.group_id"],
          "rows": 1,
          "filtered": 100
        }
      }
    ]
  }
}

Result

feature_id purpose product_id parent_product_id id code
22556 group_variation_catalog_item 52 0 14809 PV-A441030E3
22517 group_variation_catalog_item 112 0 14770 PV-20F0F6AA2
22348 group_variation_catalog_item 382 0 14616 PV-4F6624798
21912 group_variation_catalog_item 1059 0 14213 PV-36E94A966
20463 group_variation_catalog_item 3875 0 12913 PV-01592A956
20461 group_variation_catalog_item 3877 0 12911 PV-ECB19F397
20459 group_variation_catalog_item 3879 0 12909 PV-59299FDAD
20458 group_variation_catalog_item 3880 0 12908 PV-C70555C9F
20457 group_variation_catalog_item 3881 0 12907 PV-659DB19CB
20456 group_variation_catalog_item 3882 0 12906 PV-DD55F1F0C
21626 group_variation_catalog_item 23162 0 13954 PV-2534093C4
24717 group_variation_catalog_item 49265 0 16946 PV-440103524