Here is the full list of all 51 SKULL AND BONES trophies - there are 37 bronze, 12 silver, 1 gold and 1 platinum.
Unlock all trophies.
Greet players with an "Ahoy!" from the quick-chat option in a server chat room.
Spyglass or interact with La Bastide.
Complete 5 shared contracts.
Group up with two other players during gameplay.
Spyglass or interact with Ankohonana.
Activate a pirate's bonfire on 3 outposts.
Spyglass or interact with Tenina Town.
Harvest wood in 3 regions.
Hunt down at least 1 of each hostile wildlife (spear only).
Talk to 20 interactable NPCs.
Explore all zones in the East Indies.
Defeat 5 ships without leaving Open Seas region.
Explore all zones in the Red Isle.
Explore all zones in the Coast of Africa.
Meet Admiral Rahma.
Destroy flare weak point to interrupt a ship from firing flares.
Hide from attackers in a safe zone.
Sink an enemy ship while having 5% HP or lower.
Explore all zones in the Open Seas.
Cook 15 dishes.
Deal 3000 damage to towers using a spear.
Defeat an enemy and leave the zone without looting.
Finish an enemy with a crew boarding.
Show your gratitude to any NPC after talking to them.
Successfully plunder a location in stormy weather.
Sink a Privateer.
Crest a rogue wave.
Harvest metal in 3 regions.
Dance to a song performed by musicians in Saint-Anne.
Reach "Cutthroat" tier.
Discover smuggler's hideout.
Successfully capture your first Manufactory.
Spyglass or interact with Suny.
Loot a total of 50000 silver of item value from enemy ships.
Wear an outfit worth more than 5000 silver.
Stare at the full moon for ten seconds while on land.
Trade items with at least 3 players.
Harvest 10000 pieces of jute in total.
Reach Saint-Anne.
Build your first ship.
Equip your ship with armor.
Scan an object from a long distance (1400m+).
Meet John Scurlock.
Sell all your brandy.
Hit enemy ships with a spear 100 times.
Spyglass or interact with Oosten Capital.
In total, deal 30000 of collision (ram) damage to other ships.
Spyglass or interact with Jiwe.
Harvest fiber in 3 regions.
Sail 1000000 meters.