Καλησπέρα ;)
Trinity should be installable and usable alongside a KDE installation with no problems,
but it is also the work of packagers to ensure compatibility.
Now it's been a long time since I last used a distro with apt, so an actual
Devuan/Debian user could probably say something more helpful on this topic, but:
You're saying that installing tdebase-trinity wiped out your KDE installation. AFAIK
there is no reason for this to be done unless there was some sort of package conflict (and
that's one reason that I like Slackware). You could leave an issue on the Trinity
Gitea Workspace (
https://mirror.git.trinitydesktop.org/gitea) so that the problem (if it
is a problem on Trinity Project's part) is dealt with.
--
Mavridis Philippe