@codewiz I think libvirt manager has xml support for filesystems as a way to attach disk storage.
I don't know if it can be used to accomplish what you described (as in I've never done that). However there is the ability to mount qcow2 disks directly onto a linux filesystem via qemu-nbd so I don't see why what you described wouldn't be possible.
I'll look into this later today if you haven't found out an answer.