There is indeed a big difference between Hyper-V and VMware. The idea of an off-host backup proxy is to take data processing of the production Hyper-V host. In this mode, the off-host shifts the backup and replication load to a dedicated machine (the off-host proxy), Basically, it retrieves the VM data from the source, processes it and then transfers it to the destination.
This process is not the same as Backup from a Storage Snapshot integration that we have with VMware. The underlying backup architecture on Hyper-V (until 2012R2) is also completely different. Maybe in 2016, with the new backup architecture, things could change but that would require a few worlds come together
If you want more information on this, please check https://helpcenter.veeam.com/docs/backu ... tml?ver=95