Sex fetishist trannies who morph into their wives are generally heterosexual. Bill and Tranma went to school together so its the old school ties/upper echelon of Adelaide society that likely binds them. And possibly a paedophile ring.
Yeah, I had something like being 'old molesting buddies' in mind. A friend of 60 years when asked to describe him as a person says this:
“I guess you'd have to say a bit quiet, a bit reserved, pretty athletic, pretty studious," seems like he thinks his friend's most important, best quality is he can keep his mouth shut. So much he named it first and twice.
I will push back somewhat on two points you made here, though. Personally think he's been skinwalking his daughter, not his ex wife, down to choosing a similar name to her (and maybe more similar when he chose it, he transitioned, when she was still a minor, and I wonder if she went by 'Jessie' as a child?).
And while they're generally heterosexual, there's a very common phenomenon that's part of the medical literature on AGPs going back to when Blanchard et all were more free to study them called pseudo-bisexuality. When an AGP is deep enough into his paraphilia, the sex of his sexual partners stops mattering nearly as much as their willingness to play along with the woman LARP, because the AGP is lusting after himself, or the idea of himself as a woman, more than any partners. The people he fucks become props, and they matter only inasmuch as they manage to facilitate the fantasy of himself as a hot woman.
Now for a lot of AGPs the main fantasy is being 'lesbians,' which needs another woman (usually straight or bi when they can't browbeat a real lesbian into sex she doesn't want...actually in practice usually ersatz, T4T) to play along and call it lesbian sex, but plenty will also fuck men because they think that's what women are
for and being a promiscuous fuckdoll for men to use becomes one of their roleplaying scenarios, because sex with real women can ruin the illusion and make them hyper-aware of how fucking male they are while men can make them feel small and 'feminine' in comparison, and because there are quite a few men out there who are eager to convince themselves that 'chicks with dicks' is a real thing and their lust for cock totally isn't gay and so are enthusiastic participants in validating the AGP's 'womanhood' in order to prop up their symbiotic delusion of 'no homo' while fucking another dude.