Can any shed any insight. I am trying to do ASR for various VMs on 2 on-prem HyperVs and one of the vm's is not listed when you are trying to select the vm's. I am able to see all others and currently have many replicating properly.
This could be that the VM is not in running a supported configuration. It could be that you have hit a limit within your subscription, such as using a single storage account for all VMs. Check here in the support matrix for ASR.
I wrote a lengthy article (32 pages) on ASR start to finish a month or so ago and it covers all the common pitfalls and how to fix or avoid them.