UE4 crashes when playing in editor. Steps to Temp Fix:
Open PXR_HMDFunctionLibrary.cpp
Find Function FPicoXRHMD* UPicoXRHMDFunctionLibrary::GetPicoXRHMD()
Find PXR_LOGE(PxrUnreal, "GetPicoXRHMD Failed!")
Add the line below:
PicoXRHMD = static_cast<FPicoXRHMD*>(GEngine->XRSystem.Get());
Compile with VS.
Bug breakdown - PicoXRHMD is not set in the Editor - nullptr. Causes crash.
Get XR system anyway as a Dev solution.
Assign XR system to Pico HMD variable.