Here is the full list of all 14 Submerged: Hidden Depths achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Collect all Creatures
Collect all Boat Boosts
Collect all Relics
Collect all Diaries
Visit all Landmarks
Use all Lookouts
Put a Flower in your hair
Change Hair Style
Change Body Style
Finish the Campaign
Collect all Styles
Collect all Flowers
Change Boat Style
View a Relic at the Home Base