Hi,
These are available:
epel = goldendict, vlc, xfce4-clipman-plugin
rpmfusion = virtualbox
so if you install:
dnf install epel-release
and then visit rpmfusion website and add their repository, then you will have all the packages you need. Goldendict is only in EPEL8, to get it for Rocky 9 would mean making a package request on EPEL site to get it added for EPEL9.
Use https://pkgs.org to search for packages that you might need. All the above that I mentioned can be found there as being available for either EPEL8 or EPEL9.
Virtualbox can also be downloaded and installed from the official Virtualbox website as well.