iSER was a feature of StarWind VSAN for Hyper-V. It has pretty much always been "Test feature". NVMe-oF target will be coming in the next build. I am not sure if it needs a new license. NVMe-oF on Windows is in test mode. In the next build, hopefully, the production-ready target will arriv...
I am sorry to inform you that there's no iSER support so far.
It is still the same build now. Please wait for the next build where NVMe-oF/TCP is going to be introduced.
You need to ensure the communication. Unfortunately, I was never doing that (it seems to be part of the end-user world).
In most cases, I just converted a VM from my server to the cloud and vice versa. Give it a shot, maybe it works if you can communicate from your servers to Azure.