The main point is the destination VM to be able to ssh to the source machine. An easy way to check would be to try ssh from another VM in the same VM network.
That said, the potential problems that I can think of:
- there must exist a route from the VM network to the source machine network, i.e. the VM network must not be isolated (neither the source machine network, obviously)
- both networks must not be VLAN isolated
- firewall settings on the source machine (as discussed in the thread)
- firewalls between the destination and source machines
- using incompatible IP versions (e.g. source is IPv6 only, destination is IPv4 only)
There may be others, too. I am not a network expert.
HTH
Plamen