I have found a way to get into the Editor if you are stuck loading in?
Go to the engine.ini and change the RHI to dx11 in the config file.
Boot up the engine.
When in the engine change it back to dx12 and change the scaling back from mobile and setup your rendering setings and shaders and lumen, nanite etc again.
It will reset a lot of your stuff but its allowing me to get into my project at least.
Epic have wrote back to me so when I get a response I will let you know what I am told in way of a fix.
Should work for you for your game too.