Windows are very sensitive with hardware, mainly with CPU.

If you change, you break.

It is not the virtualization system fault.

For libvirt/kvm you can use the CPU kvm64 that hidde some specifics features from the operational system.

In this case it is easier to migrate VM from host to host.

You can use the migration feature from libvirt to test if the 2 hosts are compatible for migrating your windows VM.

If libvirt tells you that it is not compatible and you copy the VM - it would break your VM.