what's a HSTS and how is it different from the modern troon?
A homosexual transsexual (HSTS) is an effeminate gay man who has seemingly imprinted on female social roles and wishes to actually be a woman and have heterosexual-seeming relationships with straight men. Perhaps some wires got crossed in early socialization and they hold some unspoken belief that the only way to have Prince Charming carry them off to a white wedding and or deep dicking is to become Cinderella. Back in the day when the idea of being "openly gay" and just dating other gay people was unthinkable, it made a kind of neurotic sense. And much like whatever middle eastern shithole chops cocks to turn immoral gay men into true and honest women, I can see how someone who has internalized the idea that being a homo is the worst possible thing but who can't shake their desire for men could then try to rewrite reality into "it's natural for women to desire men, so I must be a woman somehow. Maybe the brain has a sex separate from the body!"
The pooner equivalent would be a butch dyke who uses similar childlike logic to conclude "me like motorcycles and pussy, me must be man."
AGPs, or autogynephiles, are heterosexually-attracted men with a fetish for being feminized that becomes an obsession they're determined to live 24/7, damn the consequences. As the root of the fetish is humiliation and social deviancy, they often hold really weird ideas and resentments towards women. The classic form of this is the retired military man with a wife and kids who blows it all up to go tranny around the time most of his peers are buying their mid-life crisis motorcycles. Though heterosexual (in the sense of "looking at naked pretty lady pictures produce boner, looking at naked handsome man pictures does not"), they may hook up with their fellow trans-identified-males and cope by claiming it's "sapphic", and some do let men fuck them as part of their fantasies of ultimate feminization, but they're not interested in the man, just the fetish of being "treated like a woman."
There wasn't really a widespread female equivalent to this until recently, though
Poppy Z Brite is an example of pre-internet auto-androphilia. Now that the internet has popularized man-on-man erotica for women, their numbers have exploded seemingly overnight.
In this post-internet post-trans rights age, the categories have collapsed somewhat and the popular understanding of what it means to "want a sex change" has shifted. There are many younger (often cracked-egg grooming victim) AGPs now, there are gay boys who have also been groomed into feminization fetishes despite not sharing the attraction to actual women that drive hetero AGPs, fanfiction and a tumblr culture that insists that you must be a boy if you enjoyed that fanfiction has lead to not just an increase in AAPs but also girls who believe they're not-girls because only a gay boy could like the sight of two androgynous pop stars teasing a kiss, as well as girls wanting to transition for various social reasons, etc. But the idea of "some straight people have a fetish for imagining themselves as the opposite sex and go batshit with it along somewhat predictable patterns" remains useful, even if it's anathema to troons now. Credit to
Ray Blanchard who came up with the names for the two types.