Here is the full list of all 31 Windward achievements. It takes around 40-50 hours to unlock all of the achievements on Windows.
Sink another player in PvP.
Complete the Strange Diagram quest.
Equip an item that will push any stat above 1000.
Achieve the Admiral reputation standing with any faction.
Drive out pirates from a level 39+ region.
Sink a pirate captain in a level 39+ region.
Unlock all ships.
Capture a level 9 or higher region in a co-op match.
Completely drive out pirates from a level 9+ region.
Become a true pirate. Arrr!
Make a town grow in size.
Establish a foothold in a region where your faction has no towns.
Drop Grogolov on top of 3 or more enemies.
Opt out of a PvP match by using a White Flag.
Successfully complete a commission to place a Guard Tower near a town.
Repair your ship while obscured by fog.
Hire a follower.
Complete 50 commissions.
Defeat 100 ships.
Find and equip your first epic item.
Defeat a Pirate Captain.
Defeat an enemy by yourself without taking any damage.
Defeat two enemies back to back.
Achieve a skull kill rating.
Complete two consignments at the same time.
Defeat 5 pirates.
Upgrade your ship.
Open a Sealed Letter.
Do your first trade run.
Complete your first commission.
Customize your ship's look.