exactly same issue on desktop with 2x2080ti asus strix oc, 1080ti, 980ti, i9 9900k, 64gb g skill qvl ram, samsung 970pro… new hardware, msi meg godlike, new windows, 4 monitors, 3 on 980ti, 1 on 2080ti - and still UE forced 1080ti to use as primary until I edited that .ini to force it to use 2080ti - and then it begins freezing constantly…
EDIT: no luck with latest hotfix as well, exact same issues as on laptops