Binding Traffic to Specific Interface

[mbwmbw1337]

Is there an easy way to add a field to allow binding to an interface (eth0/eth1/eth2)? I.e. I have 3 ISPs but I only want the WireGuard traffic to flow out via one. I have tried everything from static routes to force the traffic over an interface to firewall rules. None work.

[mbwmbw1337]

Any updates on this?