Visual traits won’t have any influence on the game, however they create unique, and exceptional Pirate appearance, and are a very nice addition!
In the future game development some functionalities can be added to the visual traits as well.
Plain bandana: +1 respect
Bandana with skull: +2 respect
Gold hairs: +20 $RUM
Navy hairs: +5 Stamina
Bones shirt: +3 to Voodoo magic
Pirate shirt: +2 to respect
Skull shirt: +1 to respect