Hi,
Hope you are looking below steps.
Renaming virtual machine files using Cold Storage Migration
The files of virtual machine can be renamed on the fly when a Cold Migration is initiated from the vSphere Client, only the virtual machine's folder is renamed.
To rename the files:
Log into the VMware vSphere Client.
Locate the virtual machine in your host inventory.
Right-click the virtual machine and click Rename.
Change the virtual machine name as required.
Perform Cold migration to a new datastore of the virtual machine.
For more information, see:
For ESXi/ESX 4.x, see Cold Migration in the vSphere Datacenter Administration Guide.
For ESXi/ESX 3.5, see Cold Migration in the Basic Administration Guide.
After the migration completes, the virtual machine files match the virtual machine name configured in Step 4.
Note: If a virtual machine directory already exists on the datastore with the same name, then the target virtual machine is placed in a new directory with _1 appended.