Dual Wan Help

Hi

I have read various posts here, on reddit etc, but still unsure of best plan.  I recently added a 2nd WAN to my UDM (in balanced mode) - NextDNS runs on UDM.  What is the best way to have the traffic routed through that WAN also filtered etc.?  I had previously done a ip4 assignment, but been reading that a DoH may be an option but kina lost there.  Also, noted that creating a 2nd profile and replicating settings (but that seem clunky since I have tons of rewrites.

Your advice is appreciated.