I see the various CONFLICTS_INSTALL lines under <https://www.freshports.org/emulators/virtualbox-ose-additions/#description>
An edge case arose when I (carelessly) tested to tell whether virtualbox-ose-kmod-legacy was installable on FreeBSD 12.2-RELEASE-p7:
root@freebsd:~ # pkg info -x virtualbox
– careless because the test, in response to <https://forums.FreeBSD.org/threads/81892/post-529422>, was in a VirtualBox guest (not on real hardware).
> … there should probably be a conflict between guest additions
> and the kernel module. …
I'm not sure if anything is actually wrong in this case.
Does having additions and the kmod installed at the same time cause issues?
Both are also not loaded by default even if installed. I'd say that trying to load them at the same time is a configuration error, preventing it goes beyond the package management tools duties.