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