SELECT 
  pfv.feature_id, 
  pfv.product_id, 
  pfv.variant_id, 
  gp.group_id 
FROM 
  cscart_product_features_values AS pfv 
  INNER JOIN cscart_product_variation_group_products AS gp ON pfv.product_id = gp.product_id 
  INNER JOIN cscart_product_variation_group_features AS gpf ON gpf.group_id = gp.group_id 
  AND gpf.feature_id = pfv.feature_id 
WHERE 
  pfv.lang_code = 'vi' 
  AND gp.group_id IN (
    16089, 14147, 14069, 15890, 17236, 12527, 
    12550, 13821, 17087, 14364
  )

Query time 0.00817

JSON explain

{
  "query_block": {
    "select_id": 1,
    "nested_loop": [
      {
        "table": {
          "table_name": "gp",
          "access_type": "range",
          "possible_keys": ["PRIMARY", "idx_group_id"],
          "key": "idx_group_id",
          "key_length": "3",
          "used_key_parts": ["group_id"],
          "rows": 33,
          "filtered": 100,
          "index_condition": "gp.group_id in (16089,14147,14069,15890,17236,12527,12550,13821,17087,14364)"
        }
      },
      {
        "table": {
          "table_name": "gpf",
          "access_type": "ref",
          "possible_keys": ["PRIMARY", "idx_group_id"],
          "key": "idx_group_id",
          "key_length": "3",
          "used_key_parts": ["group_id"],
          "ref": ["dev_db.gp.group_id"],
          "rows": 1,
          "filtered": 100
        }
      },
      {
        "table": {
          "table_name": "pfv",
          "access_type": "ref",
          "possible_keys": [
            "PRIMARY",
            "fl",
            "lang_code",
            "product_id",
            "fpl",
            "idx_product_feature_variant_id"
          ],
          "key": "idx_product_feature_variant_id",
          "key_length": "12",
          "used_key_parts": ["product_id", "feature_id", "lang_code"],
          "ref": ["dev_db.gp.product_id", "dev_db.gpf.feature_id", "const"],
          "rows": 1,
          "filtered": 100,
          "attached_condition": "pfv.lang_code = 'vi'",
          "using_index": true
        }
      }
    ]
  }
}

Result

feature_id product_id variant_id group_id
20031 16776 70033 12527
20031 16775 70032 12527
20031 16774 70031 12527
20031 16773 70030 12527
20031 5478 70034 12527
20054 16846 70126 12550
20054 5405 70127 12550
21469 22715 75154 13821
21469 22714 75153 13821
21469 1768 75153 13821
21748 23481 76046 14069
21748 1287 76045 14069
21830 1174 76388 14147
21830 23747 76387 14147
22081 798 77289 14364
22081 24652 77288 14364
22081 24653 77290 14364
23771 37107 82560 15890
23772 37107 82562 15890
23771 37105 82559 15890
23772 37105 82562 15890
23771 16847 82559 15890
23772 16847 82561 15890
23771 37106 82560 15890
23772 37106 82561 15890
23913 38129 83177 16089
23913 38309 83178 16089
23913 38310 83179 16089
23913 38311 83180 16089
24836 47652 86606 17087
24836 47685 86607 17087
24836 47686 86608 17087
24991 49119 87172 17236
24991 49118 87171 17236
24991 49018 87170 17236
24991 49120 87173 17236
24991 49121 87174 17236