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