Based on current data from the Kingdom Come: Deliverance II community, players can locate raven feathers in several, often respawning, locations:
A hard-to-reach chest in the chapel at the top of the tower contains reliable amounts of feathers, which may respawn every 24 in-game hours. raven feathers buy
A bag containing 15 feathers can be found southwest of the Troskwitz Cemetery. Based on current data from the Kingdom Come: