Based on the information provided, the film 'Engineer Gof' does not contain identifiable LGBTQ+ characters or themes. Therefore, an evaluation of its portrayal of queer identity is not applicable.

The film "Engineer Gof" does not feature any identifiable transsexual characters or themes. Its narrative focuses on a scientist's invention of a thought-reading device and its societal implications, without touching upon gender identity.

The movie does not contain any action or adventure elements.

The film's source material and character origins are not provided. Without information on prior canonical or historical gender for any character, it is impossible to identify an instance of a gender swap.

There is no historical or canonical evidence suggesting that any character in the 1935 Soviet film "Engineer Gof" was established as one race in source material and then portrayed as a different race on screen. The concept of a "race swap" as defined is not applicable to this film.