Having purchased EyeTV 4 (8521) for macOS Catalina, there have been issues, some documented in the support forum here. I have allowed time since purchase for updates to be issued, which they have and all in all EyeTV 4 is an unmitigated disaster.
Exporting is useless.
Video stuttering
Exiting Full Screen takes at least 2 attempts before it exits.
Spinning beachballs galore.
It is an unqualified mess.
EyeTV 3 and earlier, allowed you to export in whatever format you wanted and guess what? IT WORKED
EyeTV 4 exports a file which is unreadable by any player I have tried.
EyeTV 4 is a pile of useless junk and a complete waste of money. It's as if Geniatech had absolutely no Mac software experience, but they did with EyeTV 3
DO NOT BUY.