[teleforce]

The best way to perform something like this on Layer 2 is to use Shortest Path Bridging (SPB) based on IEEE 802.1Q-2018. However the Linux kernel does not yet fully supporting this feature natively although the standard has been out for quite sometime and already being supported by commercial network solutions and the popular Open vSwitch (OVS) [1].

[1] Ask HN: Project ideas for a Linux kernel module:

https://news.ycombinator.com/item?id=35785158

[wmf]

SPB uses MAC-in-MAC encapsulation which won't help you run over Wireguard. You need some flavor of Ethernet over IP like GRE, VXLAN, or GENEVE.