Quoted from KingBW:For MAC, try this below. I don't own a MAC, but Joe Katz gave this information out recently to people with the same issue. If it works for you - great!
So that process formats a USB in a Windows compatible form and then copies the files onto that USB.
Just manually doing what Unebootin does?
Since moving up to Catalina, there have definitely been some compatibility issues come about.