I've seen threesomes where there are two ukes, two semes, ect.
But they always seem to be small/girl and rough/big. What I'm looking for is a uke that's big and manly, while having two seme that either look similar to the uke or look more like ukes.

Maybe Koi no kawaki ?
That's the only one that comes to my mind with those requests.

Ch. 7 of Sex Therapist may fit ~ I mean you can tell who the uke is by looking but he isn't as girly as most in the threesome plots.

try all Takao Hiroi and Kamuro Akira's collaborated mangas. There is threesome and foursome too

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Fallintrash the "uke" actually reverses, and although he's got long hair and is described as someone who'd make a good bride his height and build are similar to the other 2