CanonRumors reports that a “good source” is reporting the inclusion of both quad-pixel autofocus and global shutter capabilities with the rumored 2021 release of the top-of-the-line mirrorless sports body to come.
Quad-pixel autofocus would allow for two things, one of which is important. It would allow for a higher resolution of autofocus data, which is already at a very high level with Canon’s dual-pixel mark II technology. More importantly, it would resolve both vertical and horizontal lines with equal ability. As of right now, the mirrorless cameras autofocus very well on one axis and can struggle in the other under some conditions.
Global shutter allows for every pixel to be read simultaneously, cutting out all effects of rolling shutter during short exposures. Its effect is less profound during longer stills exposures, which of course are still vulnerable to subject movement. For video, exposures are typically longer (about 1/50th of a second).