One way that I can think of having PSA-V (Hyper-V) as a cold site VPN server is by importing the configurations from the physical appliance, and doing a DNS record change for redirecting the user connections to the virtual appliance during the time of disaster.
You can also have different hostnames pointing to physical and virtual appliances, which we can add it as connection URLs on the Pulse Client, then the pulse client will do a automatic fallback to the DR site VPN server, if the primary one is not reachable or resolvable.
Another way is by having a load balancer to route the traffic to the virtual appliance at the right time.
Since we cannot join both physical and virtual appliances as a cluster, configurations has to be synced either by using push configuration setup on the physical appliance.
Regarding the licensing, you have to purchase subscription based platform license to activate the CPU cores, which is determine the max.no of supported user sessions and an user license just like you got one for the physical appliance.
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