So far there is no “proper” solution. The issues is related to HMD Headset/Controllers not connected on OpenXR init.
You still can run project with OpenXR plugin Enabled without HMD attached by using -nohmd parameter.
Create the shortcut to your UnrealEditor.exe, then add path to project and -nohmd.
Like:
C:\UnrealEngine\Engine\Binaries\Win64\UnrealEditor.exe d:\MyAmazingProject\MyProject.uproject -nohmd