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