It can't.
I asked about this a year ago and while it seems the ability to bind Wireguard to an interface is present in the kernel in FreeBSD 14, the functionality doesn't exist in OPNsense for it.
In my use case, I switched to IPsec and while it has its own difficulty in configuration in OPNsense, has been quite reliable for the desired purpose.
I asked about this a year ago and while it seems the ability to bind Wireguard to an interface is present in the kernel in FreeBSD 14, the functionality doesn't exist in OPNsense for it.
In my use case, I switched to IPsec and while it has its own difficulty in configuration in OPNsense, has been quite reliable for the desired purpose.