We have a point to site VPN gateway, we use it to RD to the VM in a region with the private IP. We have a second VM in a different region. I've created a vnet to vnet vpn. From the first VM I can RD into the second using the private IP. But I was hoping to be able to connect to the second VM just using the point to site VPN.
Do you know if it is possible and what I'm missing?
It's possible that you could configure VNet peering with Gateway transit in a hub-spoke network topology in Azure.
To do this:
allow gateway transit
.use remote gateways
.Document states, Gateway transit
is supported for both VNet Peering and Global VNet Peering (preview). You could refer to more details about VNet Peering with Requirements and constraints.
Once both peerings connected, you could redownload and reinstall VPN client on the local machine to make the route update.
Spoke VNet configuration and test result. You could RDP to another VM with private IP but ping usually blocks by the windows firewall.