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 (
    67841, 68817, 67790, 67789, 67788, 67787, 
    67786, 67785, 67784, 67783, 67782, 
    67781, 67780, 67779, 67778, 67777, 
    67776, 67775, 67774, 67773, 67772, 
    67771, 68694, 68693, 68661, 68532, 
    68124, 68123, 68692, 68662, 68573, 
    68531, 68374, 68361, 68199, 67871, 
    67844, 67843, 67840, 68201
  )

Query time 0.00021

Explain
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
1	SIMPLE	p	ALL	PRIMARY,idx_group_id				376	Using where
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