Currently, most of the skeleton curse related cosmetics are earnable through pvp related commendation, and while it's in line with the way the skeleton curse is unlocked, I think there should also be other more pve oriented ones.
For exemples :
- season related commendation, similar to some of season 13 but for every seasons
ex : shadow skeleton bones, a skull with kunais and ninja stars, a weathered samurai armor, etc.. for season 14 ; a fishbowl upper body, bones similar to that of the old skull's, etc.. for season 15, etc... - tall tales related commendation, those could simply be cosmetics given along the rrward for getting all commendations for a tall tales
ex : LeChuck's crew bones for completing The Legend Of Monkey Island, the cursed captain's clothing's and/or bones similar to Wyvern (POTC 2) for completing A Pirate's Life, etc... - other companies related commendation
ex : "retrieve X merchant manifests while wearing the skeleton curse and flying the Reaper's Bones emissary flag" that would unlock a "disgraced merchant set" with worn and thorn merchant clothings
