A Yuba Mundo has extra long chainstays. Chain line should be less of an issue with that.
The chain/belt line on a Yuba Mundo should be even easier with a Rohloff hub, a BBSHD and a Veer belt. I might need a machine shop also but am willing to try. VEER makes belts that screw together and I saw a video on YouTube that had a Yuba Mundo with one of their belts on it.