Here is the full list of all 12 ABZU achievements. It takes around 3-4 hours to unlock all of the achievements on Windows.
Breach the water on the back of a blue whale.
Discover the polar region.
Release fish from all the hidden pools.
Add all secret shells to your collection.
Complete the adventure.
Ride the Great White Shark.
Find all the meditation statues.
Discover those that lurk in the abyss.
Witness predation while meditating.
Burst 15 fish schools in the jetstream.
Perform a flip while riding a creature.
Leap from the water.