Sorry don’t know how to fix but…
I’ve been experiencing something like this with my Unified receiver.
It’s plugged into a monitor’s USB port, I have no reason to believe it’s faulty.
Sometimes the mouse (logitech mx2) is dead upon boot (graphical), I mean it doesn’t move. A keyboard plugged into a USB port on the same monitor is just fine.
Logging out and back in doesn’t fix it. Only pulling the receiver out and plugging back in does.
I’m positive it started before Fedora 30.
Not sure about kernel 5.0 as I’ve been using 4.20 with Fedora 29 from the start (because of my graphics).
Next time I’ll try to check system logs to see they have same error codes.