Can linux load balance between multiple routes to the same subnet?

I'm looking for a way to load balance between multiple routes for the same subnet under linux. The scenario is that we have multiple Linux machines (EC2 instances) each configured with a Strongswan VPN client. Each one has access to the same subnet on a remote site. We'd like to configure other machines to route to that subnet through those machines. But the problem is that the VPN tunnels have rate limiting associated so we don't just want to route everything through one server. It's also possible that one could go down for any reason so a solution involving a level of failover. I've been unable to find much information on the subject. Is this something that typically requires dedicated hardware, or did I miss something in iptables / nftables?