Is this a thing?

Probably not, but you could make it fairly easily. You wouldn't even need to use the modding tool.

Copy mushu.tbm, open it with notepad, and set the gravity setting to -30 (or whatever Sambo's is.) Save it as whatever you want. You're all good.

I played a couple games of it, Sambo grav is way higher than I remember it being lol. Wasn't any good, maybe a skilled player could make something of it though.