Are you on the latest windows build?
I've not tried this yet so can't comment other than I know you need to be on the latest build.
latest drivers seemed to fix it for whatever reason.
I had this problem - go to data and time settings in windows and make sure its set to auto and not manual, do a time sync and you are good to go.
I take it back, its gone back to not launching anything again! I`ve gone back to the previous build of Windows and cancelled the game pass. Its a shame as I wanted to play Metro, I`d rather wait than have to faff with the windows launcher.
As Cha1ky said, are you running Win 10 v1903, as I believe that’s a prerequisite?
Yup it was all running the correct build of windows, it updated itself and took forever doing it. Was all fine last night and this evening it didn't want to launch anything. It is a Beta after all. I got about 5 hours into Metro so I got my £1 of gameplay.
Metro Exodus on Twitter