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 (
    99000, 99001, 99002, 99003, 99004, 99005, 
    99006, 99007, 99008, 99009, 99010, 
    99011, 99333, 99334, 99335, 99336, 
    99337, 99338, 99339, 99340, 99341, 
    99342, 99343, 99491, 99492, 99493, 
    99494, 99495, 99496, 99497, 99498, 
    99499, 99500, 99501, 99502, 99503, 
    99504, 99505, 99506, 100399, 100479, 
    100501, 100502, 100853, 100854, 100855, 
    100863, 100864, 100865, 100866, 100871, 
    100872, 100873, 100874, 100875, 100876, 
    101054, 101656, 101657, 101658, 101659
  )

Query time 0.00064

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "1.05"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "f",
          "access_type": "ALL",
          "possible_keys": [
            "idx_group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.10",
            "prefix_cost": "0.35",
            "data_read_per_join": "104"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "g",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "id"
          ],
          "key_length": "3",
          "ref": [
            "nuie_scalesta_net.f.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.10",
            "prefix_cost": "0.70",
            "data_read_per_join": "400"
          },
          "used_columns": [
            "id",
            "code"
          ]
        }
      },
      {
        "table": {
          "table_name": "p",
          "access_type": "ref",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "ref": [
            "nuie_scalesta_net.f.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 1,
          "filtered": "100.00",
          "index_condition": "(`nuie_scalesta_net`.`p`.`product_id` in (99000,99001,99002,99003,99004,99005,99006,99007,99008,99009,99010,99011,99333,99334,99335,99336,99337,99338,99339,99340,99341,99342,99343,99491,99492,99493,99494,99495,99496,99497,99498,99499,99500,99501,99502,99503,99504,99505,99506,100399,100479,100501,100502,100853,100854,100855,100863,100864,100865,100866,100871,100872,100873,100874,100875,100876,101054,101656,101657,101658,101659))",
          "cost_info": {
            "read_cost": "0.25",
            "eval_cost": "0.10",
            "prefix_cost": "1.05",
            "data_read_per_join": "16"
          },
          "used_columns": [
            "product_id",
            "parent_product_id",
            "group_id"
          ]
        }
      }
    ]
  }
}