@Roaster
Sorry I got none,
Having a slice of life comedy without a hint for romance or "het" (which would work if it only body swap) is already rare.
One of the closest thing I can get is Danshi Koukousei ga Mahou Shoujo.
That's because it seems the story only revolve with the gang(where the all actually guys) being a comedy without a romance.
If it's Body swap gender bender there's alot of good one because, the story would mostly focus on the Romcom and fluff between the two main cast cast. (Can be drama as well)
Meanwhile most of the trope gender bender story is where the gender bended dude trying question his sexuality because his Best friend, Childhood friend or Rivals whatever with Romcom shenanigans.
Oniichan Oshimai is rather peculiar because not much gender bender manga would take the story as cute girl doing cute stuff or CGDCT (which is popular in Japan, and it also make it indirectly subtext Yuri).
The problem I learned from this genre is when having a romance in story, there's always that one girl where there's a very low odds she could win.
Her case is similar to that one girl as childhood friend in harem manga.
They just there to suffer where MC literally goes to the other guy because muh sexuality suddenly change after my sex changed (Just like 98% hentai plot if you read tons of it).
Its not like I am asking a Yuri ending, but if I wanted to see a straight romance I would be just go straight to a good one instead questioning protagonist sexuality as the running joke for the whole series (it's painful to see it reused multiple times).
If I want gay shit, I would just run to Yuri or at least Shounen AI. Look at Prunus girl, that was some masterpiece shit and I am a straight guy.
If you want to look at stat you can check here https://myanimelist.net/manga/genre/44/Gender_Bender
Fact already said that most of genderswap (due mention most of the top one isn't Genderswap but is a cross dressing) barely get a good score even if you call it a subjective score.
So tl;dr
Genderswap would work if
- Body swap for straight romance, this work 100% of the time because of the drama it can pull even the comedy. This was really common back then before the Romcom and questionably gay trope attacked the Genre.
- No romance plot but slice of life and comedy. Just make it whack, dumb and chaotic.
- Yuri, but Yuri always revolve around Drama. Drama is rather rough to make and making it amusing for reader is even harder. This thing is even rare and can turn most of the reader when done wrong.
- Straight romance with the dude turned into a girl following a romance with another guy. Simply there is no other girl involved because it's fucking painful to see the girl ignored in the relationship especially MC or the girl once have feelings. They just cannot win.
- Romance Comedy/Romcom aren't used 24/7. Honestly this might be subjective but I never really liked this train wreck of a genre. In gender bender they're used to make the plot progress which even pains me to see the MC slowly question his sexuality as a girl and the other guy who see him as a girl as the comedy. Make as we stare as a wall for my case.
After believing that Gender bender was a mistake, I ran into Yuri (there's lot of game to pick as well and I am playing one right now) and include some trap stuff for the LULs #nohomo.
There's honestly aren't much Genderswap games (VN) or Anime...
Kampfer was the last thing I could remember and it was actually nice but Manga suck, Anime doesn't conclude a shit, leaving you to LN as option.
That's my honest opinion on Genderswap genre
As for other recommendations.
Tensei Pandemic is the closest thing I could imagine as my perfect gender bender drama but it waste too much of its side plot with that hentai protagonist hair and lucky sukebe trope. (The ending changed my mind)
Also if you ever read Ranma 1/2, that was the earlier best Genderswap thing you could get as a "Shounen" target.
He has a someone who liked him as a girl,
He has some girls he interested with,
Romcom in an action genre.
Interestingly despite being close to harem it doesn't went into a Trainwreck mode.