Infernal Affairs does not feature any identifiable LGBTQ+ characters or themes. The narrative focuses on the conflict between an undercover cop and a mole within the police force, with all depicted relationships and character identities being heterosexual. Consequently, there is no LGBTQ+ portrayal to evaluate.

Infernal Affairs does not feature any identifiable transsexual characters or themes. The film's narrative is centered on a crime thriller plot involving an undercover police officer and a mole, with no elements related to transgender identity.

The film primarily focuses on male protagonists and their involvement in police and triad operations. Female characters in the movie are not depicted engaging in any direct physical combat or martial arts against male opponents.

Infernal Affairs (2002) is an original film, not an adaptation or reboot of existing source material with previously established characters. All characters introduced are new to this film, thus precluding any gender swaps from prior canon.

Infernal Affairs is an original Hong Kong film from 2002, not an adaptation of pre-existing material or a biopic. Its characters do not have a canonical or historical race established prior to this film, thus precluding any race swaps.