Bonjour Saladier
Ce forum est en anglais, donc je continue dans cette langue...
A P2V conversion does not affect the source machine (almost). An potential issue you might have is that the application data would differ if the VM has been used in production for a while. But generally you should be able to revert safely to the source machine.
OTOH - what do you mean the VM needs the physical machine powered on? A VM should not need that.
Regards,
Plamen