You could run VMware Converter Standalone on Machine A to capture it into a VM (let’s call that VM A) which you then run on VMware Workstation on Machine B.
However, as soon as you’ve done that, the OS in VM A will be different to the OS on Machine A, as some of the virtual hardware components will be different to your physical hardware components.
So, while any upgrade you then did in VM A should show you any application incompatibilities with the Win7 upgrade it won’t be exactly the same as doing the upgrade directly on Machine A.
VMware vCenter Converter Standalone
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