If you are going to replicate a Windows Virtual Machine you need to have an appropriate number of licenses to do so. Each install of Windows requires its own Product Key unless it a Volume License Key.
To make a copy of an existing Virtual Machine, shutdown from within the OS, not suspend and close VMware Fusion and then ctr-click the target Virtual Machine Package and select Duplicate or copy and past it to a different folder.
If you want to increase the size of the virtual hard drive on one of the copies have a look at:
In order to run two Virtual Machines copied from the other when you first run the copy make sure you say 'I copied it" when prompted so it will chance the MAC Address and then you should also change the Computer Name within Windows itself. If you're not using DHCP for the IP Address make sure you assign a different address for the Network Adapter.
You can of course use Sysprep on the Master Virtual Machine so as to be assured each copy is uniquely different at the Windows level and this is the Microsoft Supported Method of replicating installs.
Although you can use VMware vCenter Converter Standalone on the Windows Virtual Machine it's really not necessary and it takes longer then then information I've already provided. There are times that using Converter has it advantages but for what you're asking to do I do see needing it.
As to the issue of changing the SID this just isn't necessary and frankly never was and this is from the person that wrote it who now works for Microsoft and you can read about it at NewSID Retirement and the Machine SID Duplication Myth