I know that most hentai tg manga tells about a person who turns into a woman and gets rape or sex with her friend and in the end accepts being a girl or doesn’t change back into a guy in the end.
Personally I prefer three types of hentai TG manga :

1)A person who turns into a woman and turns back to normal in the end only for the other person who was having sex turn into a girl
Eg- a story from [Kakashi Asahiro] Megami no Saien first pages- http://g.e-hentai.org/s/b5af2d0a37/911853-102 http://g.e-hentai.org/s/d620acaf54/911853-103 last page -http://g.e-hentai.org/s/1f685d31fa/911853-119

Piero-cursed breasts from Chichiyoku | Desirable Breasts anthology first pages- [nhentai.net] https://nhentai.net/g/114765/66/ [nhentai.net] https://nhentai.net/g/114765/67/ [nhentai.net] https://nhentai.net/g/114765/69/ [nhentai.net] https://nhentai.net/g/114765/84/

[Sado] Onna ni Natta Ore no Shojo, Hoshii - http://g.e-hentai.org/g/946983/da037c80f3/

Non hentai one like [Tadano] Asa Okitara Onnanoko ni Natteita http://g.e-hentai.org/g/997772/ca1c8d8193/

[Amano Tamaki] NyoTai Ka!= http://g.e-hentai.org/g/709027/73b5fa5ee7/

And [Mukeikaku Syugi (Netoromorikon)] Onnanoko ni Naare!! [Digital] http://g.e-hentai.org/g/979122/eef11a594c/

2) A couple a man and a woman swap each other genders-