I know it's been asked if it's possible to mount an XL lens on a DSLR; but M43 bodies have a flange focal distance of 19.25 mm, so that seems more possible, although I haven't found a manufacturer that produces such an adapter.
TL;DR: even though the shorter FFD of mirrorless cameras solves the infinity focus problem, the small image circle of XL lenses presents the same problems as answered to the referenced question about mounting XL lenses to DSLRs.
From a flange focal distance (FFD) standpoint, yes, it is possible. But the most likely reason you haven't seen a XL-to-MFT adapter is because the Micro 4/3 sensor is much larger than the 1/3" sensor Canon XL lenses were designed for.
MFT's crop factor is 2; 1/3" sensor crop factor is 7.21. Thus the XL-to-MFT crop factor is 7.21 / 2 = 3.6. The 1/3" sensor of the XL cameras is nearly one quarter the diagonal size of a Micro 4/3 sensor.
Canon XL lenses were designed to project an image circle that would cover a 1/3" sensor with minimal or acceptable vignetting (soft vignetting). But the hard cutoff of the image circle would be clearly seen/recorded on a much larger MFT sensor. Because of this, Canon XL lenses are not generally useful on sensors larger than the 1/3" sensor used for the XL.
A likely secondary reason you can't find such an adapter is because there are relatively few Canon XL lenses on the used market, compared to the huge number and low price of DSLR lenses on the market, such as Canon EF or EF-S lenses, Nikon F-mount, not to mention the various manual focus lenses of all sorts of mounts (M42, Minolta, Pentax, etc.).
If you have an XL lens anyway and want to try it without investing into some custom adapter:
This style of adapter will likely accomodate that lens mount, although you might need to outfit it with some longer screws. Won't solve imaging circle size problems, obviously.
What could be interesting would be mounting it in front of a teleconverter of some description, since a teleconverter discards the outer part of the imaging circle anyway...