Hi Roland --
Welcome to the group!
I see you've been in touch with Support about this, but I thought I'd echo their reply here as well for everyone.
Cues and hits both support batch editing of the Fade Out Time value.
You can also batch edit End Time, however this is limited to when all of the selected cues/hits target the same audio file.
Also when you are in Edit mode in Go Button, the "gear" menu has "Select All Cues" and "Select All Hits" items, which give you quick ways to get them all selected for batch editing.