I know where you mind is going, but lets keep things PG here.
Serious question though if I had a legitimate production reason to have an XXL and an XXL Pro go at a piece of stock at the same time what where one machine 1/2 while the other machined the other half…
Things I’d like to know X direction “throat” clearance and “travel”… meaning is there any difference between how much either machine can fit along their X axises and how far they can travel on them.
Y- “reach” does one machine have slightly more reach than the other so that Y- impacts could be avoided if not using boundaries.
Bed height… is there enough adjustment in the feet on these machines to bring the beds on the same Z plane or would each require its own custom table of independent height to make them sit on the same plane?
If you intend the piece to be a “seamless” project, you would have to be EXTREMLY careful that the toolpaths do not occupy the same space at the same time. In that case you would literally have both spindles or other parts collide.