Sandbox

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 (
    20910, 20914, 21748, 20700, 20702, 20703, 
    20917, 20704, 20705, 20706, 20707, 
    20708, 19857, 22994, 19858, 23288, 
    19859, 20486, 19860, 19820, 19863, 
    19865, 19866, 20154
  )

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}