Here is the full list of all 21 Ys II Chronicles+ achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Complete Ys II on Nightmare difficulty.
Master every achievement in Ys II.
Unlock all details for all non-boss bestiary entries.
Make all the animals in Ramia Village absolutely adore you.
Receive and eat four unique homemade food items.
Max out your money.
Complete Ys II Time Attack.
Complete Ys II on any difficulty.
Ensure that Maria is not amused.
Receive a free Short Sword.
"Measure" Tarf.
Raise Tarf to max level.
Sleep in three women's beds.
Receive money from a duck.
Slaughter ten generations of gatekeeper.
Oh God make them go away!
Completely fill the character notebook.
Find and speak with Aldow.
Eliminate all the monsters in Gila's basement.
Burn 50 villagers.
Scatter apples violently across the floor, most likely bruising them horribly.