Like he is for most of post-Dragon Ball, Yamcha is more or less dead weight here. Which is a bit of a shame really.
His role in the story is minor. He is attacked by some clones and is almost defeated for good.
But Goku and the rest save him and he helps in the fight against Android 21.
Which is a little funny since he has to work with Frieza, Nappa, and Cell. Nappa also remembers that Yamcha was defeated by a single saibaman.
I didn’t really use him in the story and online he wasn’t the greatest to use. So I didn’t spend much time with him to be honest.