Hi, I am sure I saw this done on a site.

A router a site A and a old 2 core cable which connects to router at site B. Can you use the wan modems say with a static ipv6 address on wan1 and then set to bridge to create a site to site link?

Interesting , any luck?

I'm looking into setting up a point to point ( site to site ) ubiquit Litebeam 5ac for my 2 locations ( 950meter distance ) instead of using VPN over broadband as well as letting site B use Site A Broadband for some services as Site B broadband is slow