Forcing all jail traffic through a VPN

I have a FreeBSD 12 box with some iocage jails that I would like to route through a VPN. I’m not sure how to do this. I’m not sure vlans are an option, I have a dumb switch between the server and router. I was wondering if I could just use another jail as a router for the jails that I want to go through the VPN? Thanks. --jake

This might be applicable for you.