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 (
    105398, 105397, 105396, 105395, 105394, 
    105393, 105392, 105391, 104328, 104286, 
    104277, 104276, 104275, 104273, 104272, 
    104271, 104270, 104251, 104250, 104249
  )

Query time 0.00016

Explain
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE p range PRIMARY,idx_group_id PRIMARY 3 20 Using index condition
1 SIMPLE g eq_ref PRIMARY PRIMARY 3 toolboxdigitalshop_dev.p.group_id 1
1 SIMPLE f ref idx_group_id idx_group_id 3 toolboxdigitalshop_dev.p.group_id 7