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