Multi-Wan Client VPN

[kapara]

I am looking to secure a client environment and having issues with how to properly set up a client ipsec vpn with a OPNsense unit that has Multi Wan.  What is the best way to provide VPN in the event that the primary connection goes down?

[kapara]

Is this even possible or would Zerotier be a better solution if using dual wan.  I would prefer to have WAN1 primary as it has better bandwidth.