Notes:

Blog post:  https://serialport.org/blog/installing-freebsd-2-0-5-in-a-vm/

This does boot in virtualbox, but there's not a supported NIC available.

MS Virtual PC:   just getting "Error: C:0 H:0 S:16" when it tries to load kernel

to use in qemu:

convert disk to qcow2:
   qemu-img convert -O qcow2 freebsd205-disk001.vmdk freebsd205.qcow2

then boot with:

sudo qemu-system-i386 -cpu pentium -m 16 -device ne2k_isa,netdev=net0,mac=00:00:0d:31:04:11,iobase=0x280,irq=5 -hda freebsd205.qcow2 -netdev tap,id=net0