Took the time out my day to thank you! I was experiencing the same problem with XBSX2. Haven't tried DuckStation since they did state that it wasn't compatible from the start. I mainly have PS2 ROMs backed up & my LaunchPass kept crashing with the same error- "path empty, system argument exception"
I can confirm:
download PSX2
> go through the BIOS setup
> edit your XBSX2 emulator settings in LaunchPass & reroute the destination path to your PC's PSX2 application instead of plain "xbsx2"
Try importing ROMs again & it should work. Be sure to select "use the files in the same location"
Thank you OP! Hope both instructions are clear enough. Don't know if the same applies to DuckStation
@XanderzOfficial