You can also use a fake IP for the default gateway on a wholly different segment with local segment ARP, or an IPv6 default router with 4-wrapping, or set up a

You can also use a fake IP for the default gateway on a wholly different segment with local segment ARP, or an IPv6 default router with 4-wrapping, or set up a router that uses promiscuous mode to capture all packets it receives from your “default route eth0” host. These are all irregular solutions, though, so I didn’t want to go too deep into the confusing weeds.