Knack 2 is free (to own) on German PSN (no PS+ required, just make a Germany PSN account) https://bit.ly/3enE1hT 

The game is playable in English and also includes a download of the OST

Google translates the game to "Crack 2"

Uncharted: The Nathan Drake Collection and Journey are free (to own) on US PSN (no PS+ required)
Uncharted Collection https://bit.ly/2AZPlfC 
Journey (PS4/PS3 cross-buy) https://bit.ly/2BTgu90 

Looks like you can add these free PSN games even if you got them on PS+ before. You should claim these again to own them permanently without a PS+ subscription (I claimed Journey on PS+ in 2016 and now there's no expiration date)