Yes, that's possible. Even if you somehow change your MAC address during the conversion, you can change it later on in vCenter itself.
MAC is assigned to the NIC.
When you do a vMotion the MAC is migrated, but when you use a VMware converter, it creates a new VM and MAC.
So you cannot migrate but manually change the MAC address after the new VM is created using VMware converter.
If you vCenters are 6.0U3 & 6.5 and the licensing available is above enterprise plus, you may try using vSphere replication solution for smooth VM migration across vCenter with no MAC change.
Interoperability Matrix - VMware Product Interoperability Matrices
vMotion of the virtual machine keeps the MAC address . You can Follow any of the below option
Remove the Host from vCenter 6.0 and Add to vCenter 6.5 then do migration of VM , it will have the same MAC address .
If it is in shared storage ,Map the storage to ESXi on the vCenter 6.5 , unregister the VM VC-6 and register to VC6.5 , but you need downtime ( Power off the VM ).
Using VMware converter and move the virtual machine , then change the mac address manually
You Can Use any Replication - vSphere Replication , Storage Replication , any other replication Software which is compatible with VMware
Export and Import Virtual Machine
Note that if any VMs are available on Target vCenter , check that same mac address is there or not before proceeding the migrationRAJESH RADHAKRISHNAN
VCA -DCV/WM/Cloud,VCP 5 - DCV/DT/CLOUD, ,VCP6-DCV, EMCISA,EMCSA,MCTS,MCPS,BCFA
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