Forgive me, and allow me to rephrase my question.
If ISP1 where to go down (and FW1 remains up), is it possible for OPNsense to route internet over ISP2, even though ISP2 is exclusively plugged into FW2?
If ISP1 where to go down (and FW1 remains up), is it possible for OPNsense to route internet over ISP2, even though ISP2 is exclusively plugged into FW2?