Thanks much for the info and all of your contributions in the forum and blog posts. They’ve been most helpful!
I’m guessing that the above solution requires installing dnsmasq on the host machine. This seems to cause problems with systemd-resolved which doesn’t recognize the dnsmasq process. I have worked around this by configuring systemd-resolved to always use 127.0.0.1 as the first nameserver, but that feels a bit like a hack.
The documentation on systemd-networkd and systemd-resolved are very sparse and incomplete.
Maybe I need to go back to NetworkManager or the old network interfaces systems.