To unlock the Great Barnacled One trophy in Burly Men at Sea, you simply need to play through the initial moments of the game.
Scroll right with R2/R and interact with the bottle. After the dialogue, head to the man playing the flute to the right. Then go further right and enter the orange house. Head further right and interact with the man. Go back out of the house and head left to the pier.
Now just sail right until you are swallowed up, and the trophy will unlock. This will be the first trophy you unlock in the game.