For openSUSE Leap 15.5 Kernel stable run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:frispete:kernel/openSUSE_Leap_15.5_Kernel_stable/home:frispete:kernel.repo
zypper refresh
zypper install virtualbox
For openSUSE Leap 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:frispete:kernel/openSUSE_Leap_15.5/home:frispete:kernel.repo
zypper refresh
zypper install virtualbox
For openSUSE Leap 15.4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:frispete:kernel/openSUSE_Leap_15.4/home:frispete:kernel.repo
zypper refresh
zypper install virtualbox