It looks to me that they are more a romanticized group than a historical fact, the sources (a least in wikipedia are at best poor).

If "Chinos" then they were of African and Indigenous mix, but if we take in account their supposedly attire, they could easily have descended /influenced by Muslims (the ones called Moros because their African blood) or "Gitanos" in the Andalusia region.

Indeed "Chino" wasn't a Asian term on the colonial casts.