While Trina was training the AI, Rose seemed like a perfectly acceptable name. But that was before Trina had even started college. Years later, when she felt she was finally ready to commit the ai to an appropriate chassis, assigning a gendered name seemed less appropriate.
That is, [Rose] is still called "Rose", until [Rose] specifies a name and pronouns to use. Which [Rose] seems to be in no rush to do.
It doesn't matter that [Rose]'s bust is clearly modded after a woman's. It could be considered a placholder - really, a lot could still be considered that. If [Rose] isn't wearing a wig, her Velcro look enough like a buzz cut. Her face isn't really articulated enough to make expressions - well. at least there's a bit around her eyes. Her mouth is always in that pucker.
At least [Rose] has done a lot of body language study since [Rose] has come online.
Due to a lack of "chub", [Rose]'s articulated limbs, while being anatomically proportional, look too long. The fingers are certainly longer than they should be. [Rose] also prefers to walk en pointe - or as Trina would call it, in a digitigrade stance.
While exact analogues don't make sense, [Rose] averages out to about 20 years old on a human developmental scale - as she was only loaded into the base chasis 2 years ago, [Rose] is still lacking a lot of socital interaction. And Trina... isn't really helping with that.