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 (
    11, 290, 292, 300, 303, 304, 308, 309, 
    310, 298, 334, 301, 317, 318, 46, 45, 
    9, 44
  )

Query time 0.00075

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "75.64"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "f",
          "access_type": "ALL",
          "possible_keys": [
            "idx_group_id"
          ],
          "rows_examined_per_scan": 13,
          "rows_produced_per_join": 13,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "2.11",
            "eval_cost": "2.60",
            "prefix_cost": "4.71",
            "data_read_per_join": "1K"
          },
          "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": [
            "atulecarter_atul_demo1.f.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 13,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "13.00",
            "eval_cost": "2.60",
            "prefix_cost": "20.31",
            "data_read_per_join": "5K"
          },
          "used_columns": [
            "id",
            "code"
          ]
        }
      },
      {
        "table": {
          "table_name": "p",
          "access_type": "ALL",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "rows_examined_per_scan": 49,
          "rows_produced_per_join": 23,
          "filtered": "3.67",
          "using_join_buffer": "Block Nested Loop",
          "cost_info": {
            "read_cost": "8.53",
            "eval_cost": "4.68",
            "prefix_cost": "75.64",
            "data_read_per_join": "374"
          },
          "used_columns": [
            "product_id",
            "parent_product_id",
            "group_id"
          ],
          "attached_condition": "((`atulecarter_atul_demo1`.`p`.`group_id` = `atulecarter_atul_demo1`.`f`.`group_id`) and (`atulecarter_atul_demo1`.`p`.`product_id` in (11,290,292,300,303,304,308,309,310,298,334,301,317,318,46,45,9,44)))"
        }
      }
    ]
  }
}