OpenBSD does not yet have kvm support, so you can run qemu, but it'll be very slow.
OpenBSD has its own hypervisor these days https://www.openbsd.org/faq/faq16.html
Re:OpenBSD 6.5
by infiniteseeker on Wednesday April 24, 2019 @02:33PM
(#19741439)
Do you know how VMM performance compares to something like KVM2?
KVM has more than a decade of performance enhancements from companies like rhel/intel/google.
It will definitely perform better. But that doesn't mean you shouldn't experiment and see if the performance hit is something you can accept.
Not sure if this helps, but OpenBSD does have vmm/vmd. Some have reported success running Docker within a Linux guest. https://medium.com/@dave_voutila/docker-on-openbsd-6-1-curre...
Doesn't help with the desktop OS part though.