Making a clone with the VMware Converter is a documented alternative to consolidating large snapshots. I don't see Exchange being overly relevant - services on the guest should be oblivious to such changes. I know I've done this with a large file server before.
The more manual option, however, the one I've used in the past, has been to clone the disk directly from the host, as per this document:
You would then edit the VM, delete the existing disk and add the new one. Theoretically this should be much faster and create less load on the server.
Think about the time this would need. I've had servers offline for conversion for eight hours. If that was an "alternative" to spending 12 hours doing an online consolidation, I would rather just consolidate overnight.