Based on the provided information, there is no content available to assess the portrayal of LGBTQ+ characters or themes in 'Greta, the Misfit Greyhound'. Therefore, no depiction can be identified.

The film "Greta, the Misfit Greyhound" (1963) is a short film centered on a greyhound dog. There are no identifiable transsexual characters or themes present in the narrative, as the story focuses entirely on the animal protagonist and its reluctance to race.

The film focuses on the story of a greyhound and does not feature any human or animal female characters engaging in direct physical combat, martial arts, or melee weapon fights against male opponents. No scenes meet the specified criteria.

This 1963 film does not have any identifiable source material or prior canon for its characters. Therefore, no characters exist whose gender was established elsewhere and subsequently changed in this production.

The film 'Greta, the Misfit Greyhound' is a 1963 Disney short film centered on an animal protagonist. There is no indication of human characters with pre-established racial identities from source material or prior canon that could have been subject to a race swap.