It’s about routing more than veth pairs (I mean you can also do simple bridging as other comment say, but it’s more limited), so look for BGP using ones, mainly Calico, but kube-router too.

I know there is simpler ones that don’t use BGP, but I don’t remember their names. For example there is one for AWS that uses ENI interfaces and pass them directly to containers (you’re obviously limited by the number of ENI you can attach to a particular host, then). There is also one that configures routes in the VPC routing table, and a similar one for GCP.

I've tried using Bridget[1] before, but didn't actually manage to get it working properly (although the problem was likely firewall related).

[1] https://github.com/kvaps/bridget

The built-in bridge one does. Maybe you meant something else by your question though?