Yes, this is completely possibly. See the PTC Windchill Rehosting Utility Guide. You will need to manually change the Windchill property for the Oracle database name then run the "Rename" scenario. It's should be very straightforward. The hardest part is probably duplicating the VMs, changing their names, and rejoining them to the domain. I'd recommend that you add an entry to your hosts (networking) file on the copied Windchill VM to prevent it from accessing your production Oracle DB. It will help keep you out of trouble. 
