Due to the complete absence of plot details, character information, or external web search results, it is not possible to evaluate the film's portrayal of LGBTQ+ characters and themes. Therefore, an assessment of its net impact cannot be made.

Currently, there is not enough information available regarding the plot or characters of 'Melanie, 2023' to determine if transsexual characters or themes are present, or to evaluate their portrayal. Without details on the story or character arcs, an assessment of the film's net impact is not possible.

The movie does not contain any action or adventure elements.

There is no available information regarding the source material, specific characters, or cast for 'Melanie, 2023'. Without these details, it is impossible to determine if any character's gender has been swapped from a prior canonical or historical representation.

Without information on the film's characters, their source material, or any prior established racial identities, it is impossible to determine if a race swap occurred.