The film 'Once Upon a Time in Mexico' does not feature any identifiable LGBTQ+ characters or themes. The narrative is entirely centered on heterosexual relationships and the broader plot of crime, revenge, and political intrigue, resulting in an N/A rating for LGBTQ+ portrayal.

The film "Once Upon a Time in Mexico" does not feature any identifiable transsexual characters or themes. Therefore, there is no portrayal to evaluate regarding transsexual identity.

The film features female characters who participate in action sequences, primarily Carolina. However, her combat victories are achieved through the use of firearms. There are no clear instances where a female character defeats one or more male opponents in close-quarters physical combat, such as hand-to-hand or with melee weapons.

This film is a direct sequel within its own established continuity. All returning characters maintain their previously established gender, and new characters do not represent gender-swapped versions of pre-existing figures from other source material.

This film is an original story within an established film series. The returning main character, El Mariachi, is consistently portrayed by Hispanic actors. All other significant characters are new to this installment and thus do not have a prior canonical race to be swapped from.