Voadam
Legend
You might be interested in checking out something like Frog God Games' Tehuatl for a systemless mesoamerican fantasy setting, as well as 5e, Pathfinder 1e, and OSR adventures and bestiaries.Something I keep looking for and not seeing in tRPGs is Undead as seen from some MesoAmerican, Latin American, and Indigenous sources.
Most of these might still be horror, but there’s curious space for some creative lore here - maybe that skeleton hanging out with the kids is an ancestor visiting to help the villagers out.
Maybe once a year the family visits the graves of their ancestors and imagines talking to them for advice and in a magical enough world sometimes one of those ancestors comes out of their grave to answer and then comes home for a stay for a while.
Maybe the undead aren’t evil - but are here because some of the living are and that legendary singer from three centuries ago happens to be able to channel spirits in song and so is back to help remove a new tyrant.
Also possibly something like 3.0 Aztecs, Empire of the Dying Sun or GURPS 3e Aztecs. The famous treatment is AD&D 2e's Forgotten Realms' Maztica with modules and a trilogy of novels.
Call of Cthulhu has A Resection of Time which has a huge Maya archaeology theme that is considered excellent.
Pathfinder has Tzitzimitls in one of their later bestiaries as do some others and Legendary Games has Mythic Monsters Mesoamerica and Mythic Monsters North America both in 1e Pathfinder then a big hardcover Latin American Monsters in 5e, Pathfinder 2e, and Pathfinder 1e versions.
I know that in Mutants & Masterminds 3e Atlas of Eath Prime it has things like the Llorona Weeping Woman as a supervillain.
In Gonzo post apocalyptic you have things like Children of the Sun for the Umerican setting for Dungeon/Mutant Crawl Classics RPG, Rifts South America, Rifts South America 2, their Mexican Rifts Vampires and the Rifts Spirit West.
Alt supernatural history for Witch Hunter Aztec Empire has the Aztecs resisting colonization and being a major power with blood magic, somewhat like the magical future Shadowrun with Aztechnology.
A number of these I have done out in entries in this thread, some I have not.