Honestly, I'd've figured you'd be the last person to have this question. Like, anime is practically infested with femboys to the point of being a meme.
So you're really just asking yourself "are traps gay?"
And you've handily provided an example of why trans people tend not to like that meme by somehow misgendering your own example trans dude.
Well it was more of a rhetorical question actually, but we can go into it.
Traps are a trope in anime sure and here's the thing (and I guess the answer to your question as well) if you just like a char but don't know they're a trap, definitely not gay. If you like a trap exactly because they're a trap, the part of it that does it for you is that they're a dude, that's definitely gay. If you like a char and I guess...kinda ignore their parts or overwrite them with your imagination (I know there's people who just like to pretend that traps are girls) that is prolly the most ambiguous to decide but I'd lean towards gay and in denial about it.
But here's the thing, traps in anime are not trans. Not most of em anyhow. They're closer to drag queens. They just like to dress and be feminine or they aren't even aware that they are doing that but actually identify as men in the vast majority of cases, so it actually has nothing to do with trans people and it's only about gay people.
Also my rhetorical question isn't even about traps or femboys, the closest would be like a reverse trap or a dude's soul being implanted into a girls' body, something like Cagliostro from Granblue.
That's up to everyone involved, isn't it.
I mean, I would characterize a man who is attracted to feminine qualities as heterosexual. I think that's true even when a man is attracted to or even dating someone who has a penis, or if that man is specifically attracted to feminine people with penises. But at the end of the day, it's not my choice. Sexuality is a thing we constantly have to negotiate, it's not something which has rules. At the end of the day, maintaining the purity of your sexuality is pointless. You are who you are and you want what you want, and no legalistic bargaining will change that.
In my experience, straight people fixate on these arbitrary rules because they have spent absolutely no time seriously thinking about who they are or where they fit into society.
I don't think human sexuality actually is coherent, and I think the sooner you confront that the better off you will be.
So that's interesting because that is close enough to a thought experiment I had, I called it the Ranma experiment. So I imagined if someone I already loved got Ranma'd somehow and they looked more or less the same but grew a dick, would I stop loving them all of a sudden? And the answer was a pretty easy no. But at the same time, I wouldn't love them because of the dick, I'd love them despite it, which I think is what you're describing there.
But to get to that stage you first would have had to engage in things that the dick kinda puts a block on instantly, so while in a thought experiment I could see that case, I don't think it's actually plausible in reality.
And see, I'm fine with agreeing it's not coherent but if we do that you can't have any rules any more. If no sexuality is coherent then we can't have sexuality-specific things that we need to follow since it's all an incoherent subjective mess. No more cliques and no more protected groups can exist.
