Possible to create a qube to proxy other qubes’ traffic using SOCKS?

Unfortunately, Mullvad only permits up to 5 devices in an account.

I’m in a situation where I need a different IP for a few of my qubes.

Creating many sys-mullvad NetVMs wouldn’t be an option.

Would it be possible to do something akin to the Mullvad Browser extension which allows you to set a different relay for each domain, but for whole qubes instead?

My ideia would be to have a sys-mullvad-proxy qube in which there would be a mapping (qube name x relay) like so:

“john” → relay 1
“work” → relay 2
“dev” → relay 3

and it’d somehow route traffic from a qube to its respective relay. Or, if the qube isn’t listed, it’d pick a random relay and persist.

The list of relays would be refreshed daily in a separate qube, similar to how it’s done here GitHub - maximko/mullvad-socks-list: List all active mullvad socks servers and resolve its internal addresses, and copied over to sys-mullvad-proxy.

I’m not well versed with Linux networking. Has someone done similar? How would it know from which qube the traffic is originating from? The IP address of the Qubes virtual network?

Thanks.