Here is the full list of all 12 Merchant of the Skies achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Restored botanical garden
Fed the Fish God
Supplied inns with bread and apple juice
Completed the Money Accumulation goal
Built a lighthouse
Bought a new ship
Put money into bank
Found the Giant Island
Bought an island
Completed first quest
Fueled a ship