I am looking at either D500, Fuji XT2, or EM1II as my next camera body. Nikon or EM1-2 would be the easiest to add since I already have the lenses.... Fuji I hear good things about improvement in AF, but I hope Olympus leaps ahead....
If you're looking at D500, XT2, and EM1II, I would dare say that you are not very focused on your needs...
while all "flagship" cameras for their systems (Nikon Crop, Fuji, Olympus), they serve different needs and different priorities.
The D500 is the ultimate sports and birds camera. Even if the E-M1II does a huge leap forward in AF, it will not match the absolutely sports-pro-grade AF on the D500. Nor will the E-M1 match the lens selection associated with such type of shooting. However, if you're not into high-action shooting, the D500 (and its lens collection) will be substantially heavier (and more expensive), and hardly justifiable. Esp as feature-wise mirrorless cameras today simply offer more.
The XT2 is in a way the ultimate street/photorealism camera out there. it's "retro style" controls, easier to control without looking through EVF/LV. Its focus is the weakest of the bunch (presumably), and its Zoom Lens selection is, in my eyes, problematic (to say the least), but its prime collection is spectacular. Fuji is a tool loved by photojournalists, artistic photographers and street photographers, although it can fit many more styles of shooting of course, once you get used to the dial-based interface. It's a completely different beast than the D500.
The EM1-II, as a successor of the EM1, is a more of a "Standard" camera designed for people looking at the best compromise between quality and size (and weight). With its (alleged) handheld High-Rez mode, it will allow to compensate to some degree on its smaller sensor for landscape shots, and provide a good "all around" camera. Hopefully there will be a substantial enough improve in AF speed to make its "all around" support action shooting better, but don't think it will be your favorite sports camera tomorrow.
While I could see why comparing flagship cameras in similar price range makes sense, I think the decision on which one you want, is barely relevant to the specifics of the EM1-II, but to what type of camera you are looking for. A sports crop DSLR, a retro mid-size system focused on manual controls, or an overall system with good zoom range and good size/quality ratio.
I chose the EM1 over the XT1 and 80D (Which I owned) for that reason. I would choose the EM1-II over XT2, 7DII/500D, for the same reason.