I’ve submitted a bug report and am attaching the USD.
What happens
After importing the USD I confirm both geo and material variants work properly.
I then modify the transform of the USD Stage child actor. Haven’t determined the exact sequence of steps, but eventually switching the Material Variants is broken and occassionally causes an editor crash.
mult_Variants_USD.zip (1.9 MB)
Working
imgur dot com/a/Bp45TJD
Broken
imgur dot com/a/pcGwjLo