Oracle VM VirtualBox is a hosted hypervisor for x86 virtualisation.
Supported guests include BSD, Haiku, Linux, OS/2, ReactOS, Solaris and
Windows.

emulators/virtualbox-ose is recommended for most use cases.

emulators/virtualbox-ose-legacy is for exceptional legacy (5.2.x) cases.

<https://www.virtualbox.org/wiki/Changelog-5.2> emphasises that
5.2.x is no longer supported by Oracle.

Guest Additions are available:

    emulators/virtualbox-ose-additions-legacy

For the Extension Pack: FreeBSD is not a supported host platform.
Installation of the Pack will not extend the feature set.