Multi WAN question/solution/advice?

[zo0]

Hey folks,

I am trying to do something a bit weird(?) so please excuse the heretical scenario I'm about to share with you.

I have two WAN on my physical opnsense router, default one connects to internet normally, the other one is a VPN gateway. (WAN and WAN_VPN)

My goal is to setup a server or some sorts, that can route the traffic through the VPN gateway, both from internal network and externally. So
Client -> Internet -> [shadowsocks?wireguard?squidproxy?] -> OPNsense -> [Wireguard] -> external VPN Server
Also
Client -> [shadowsocks?wireguard?squidproxy?] -> OPNsense -> [Wireguard] -> external VPN Server

Basically Client obtains the IP of the external VPN server in the end.

Now I looked up the forums for people with similar issue, and there are a couple like routing a specific LAN through the VPN gateway which works fine but I'm out of my depth for what I want to do.
I thought it would be simple at the start but the more I got into it, the more complicated it seems to be and now I am even questioning if this is even technically possible.


Has anyone made this setup work before? Or something similar?
Any help is appreciated!