Hi there, I will post the list here so everybody can see it because this question pops up all the time:
Buccaneers of the Caribe = Pirates of the Caribbean 2003 vanilla game on Maelstrom engine (kinda broken, not recommended)
Caribe Stories = Caribbean Tales 2006 vanilla game on Maeltstrom engine (works great, much recommended because it has fixed all the stability issues of the original)
Caribe Stories Historical Immersion = Historically accurate mod for Caribbean Tales from 2006. Brings jungles to the game and also a lot of other historically accurate stuff
Lost Ships City = City of the Abandoned Ships 2009 vanilla game on Maelstrom engine (works great, much recommended because of fixed stability issues of the original)
GOF 1.2 = The biggest mod in the English community for COAS, includes new characters, ships and items
ERAS 2 = Based on GOF 1.2 and is a historical accurate adaptation of GOF 1.2 but much was implemented into it afterwards
GOF 2.0 = A not historical accurate version of GOF that was a bit stripped down compared to GOF 1.2 in terms of additions to the game
GOF 2.5 = An improved version of GOF 2.5 but most say that it brought more problems than it solved, so not as beloved my the community
New Horizons = most up-to-date game on Maelstrom, probably the richest overall mod/game from the list, includes the original POTC from 2003 and so much more, including new storylines, items, ships, characters and will soon feature the biggest map of all games since it's still actively developed. New storylines only available in the Russian community will also be implemented later this year
I hope this explains everything, I will edit the post of there is something unclear or you need further information.