>>112277143Option A;
Metatton is literally transitioning, and Mettaton is a ghost transitioning into a robot body.
Option B;
>Tranny (or trannie) is a term for a transgender, transsexual, transvestite, or cross-dressing personand metatton fits into that description, and there reasons to suspect that they (yes they canonically go by they/them pronouns) were a female ghost going by the decoration coding of their house.
So yes, it is a tranny robot, because they weren't born a robot, but is transitioning into one.