I had to do a little digging on this, but the Quixel Bridge for UE5 is built into UE5 and it doesn’t work through the stand alone desktop Quixel Bridge.
Go to the Cube with green plus sign button in the top tool bar and select Quixel Bridge from inside your project in UE5. You will likely need to sign into your Epic Games account when doing this.
This youtube video should help:
