I have the same problem Failed to rename network interface 2 from 'enxXXXXXXXXXXX to 'wan': Device or resource busy
I noticed the following line in the journal that before udevd fails, systemd-networkd[293]: enxXXXXXXXXXXX : IPv6 successfully enabled so I tried to disable ipv6 in /etc/sysctl.conf by setting net.ipv6.conf.all.disable_ipv6 = 1 net.ipv6.conf.default.disable_ipv6 = 1 net.ipv6.conf.lo.disable_ipv6 = 1 which after rebooting solved the problem. Not sure if I stumbled upon the right solution but I hope it helps.
