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 (
    908, 3090, 2372, 2752, 1143, 2359, 2559, 
    2363, 2845, 2822, 2603, 3136, 2253, 
    2367, 2854, 2751, 2809, 2255, 2587, 
    2927, 2729, 2761, 3140, 1542, 2374, 
    2694, 3026, 3142, 853, 2812, 3096, 1540, 
    1544, 2736, 4887, 2723, 2829, 2742, 
    3556, 2251
  )

Query time 0.00427

JSON explain

{
  "query_block": {
    "select_id": 1,
    "cost_info": {
      "query_cost": "58.31"
    },
    "nested_loop": [
      {
        "table": {
          "table_name": "p",
          "access_type": "range",
          "possible_keys": [
            "PRIMARY",
            "idx_group_id"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "product_id"
          ],
          "key_length": "3",
          "rows_examined_per_scan": 42,
          "rows_produced_per_join": 42,
          "filtered": "100.00",
          "index_condition": "(`softwarepirmam_hewadelivard_cscart_4`.`p`.`product_id` in (908,3090,2372,2752,1143,2359,2559,2363,2845,2822,2603,3136,2253,2367,2854,2751,2809,2255,2587,2927,2729,2761,3140,1542,2374,2694,3026,3142,853,2812,3096,1540,1544,2736,4887,2723,2829,2742,3556,2251))",
          "cost_info": {
            "read_cost": "24.71",
            "eval_cost": "4.20",
            "prefix_cost": "28.91",
            "data_read_per_join": "672"
          },
          "used_columns": [
            "product_id",
            "parent_product_id",
            "group_id"
          ]
        }
      },
      {
        "table": {
          "table_name": "g",
          "access_type": "eq_ref",
          "possible_keys": [
            "PRIMARY"
          ],
          "key": "PRIMARY",
          "used_key_parts": [
            "id"
          ],
          "key_length": "3",
          "ref": [
            "softwarepirmam_hewadelivard_cscart_4.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 42,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "10.50",
            "eval_cost": "4.20",
            "prefix_cost": "43.61",
            "data_read_per_join": "16K"
          },
          "used_columns": [
            "id",
            "code"
          ]
        }
      },
      {
        "table": {
          "table_name": "f",
          "access_type": "ref",
          "possible_keys": [
            "idx_group_id"
          ],
          "key": "idx_group_id",
          "used_key_parts": [
            "group_id"
          ],
          "key_length": "3",
          "ref": [
            "softwarepirmam_hewadelivard_cscart_4.p.group_id"
          ],
          "rows_examined_per_scan": 1,
          "rows_produced_per_join": 42,
          "filtered": "100.00",
          "cost_info": {
            "read_cost": "10.50",
            "eval_cost": "4.20",
            "prefix_cost": "58.31",
            "data_read_per_join": "4K"
          },
          "used_columns": [
            "feature_id",
            "purpose",
            "group_id"
          ]
        }
      }
    ]
  }
}