Careful with P2V or V2V migrations!
In general, it will work top-level but what is hidden under the hood are drivers for a specific Hyper-Visor. In many applications time is not a biggy but for VoIP we need exact time keep drivers which simulate the CPU heartbeat inside the VM. Also, you don't wish to have VMware drivers installed in a Hyper-V for example.
My advise: Take a backup of the current install, create a new VM in the new Hyper-V and restore the backup.