Shang-Chi is trying to recover his half-sister who is a mutant (think Green Lantern constructs except using a flute) while Wolverine is trying to convince her to go to Krakoa. They come to blows. Neither are going all out, but they aren't taking it really easy either. In the end, Shang-Chi clearly wins on points after he almost defeats Wolverine by accident - kicking Logan harder than he meant to and has to save Wolverine from falling off a cliff.
Shang Chi came out looking MUCH better as fighter, and much faster and more skilled.
Logan couldn't land ONE SINGLE strike, whereas Shang Chi landed punches and kicks. Whoa.