I've used a similar commercial implementation. They're sold as USB or KVM Synchronizer. Some will control 4 machines. The one I had was limited to 2x2 or 4x1 ar

I've used a similar commercial implementation. They're sold as USB or KVM Synchronizer. Some will control 4 machines. The one I had was limited to 2x2 or 4x1 arrangements for the edge switching. Not ideal for a multi-monitor setup, but still pretty cool. I have future plans to combine it with an HDMI multi-viewer to setup a compact gaggle of machines. They were quirky in their implementation, but it still felt cool to have it all done in a little USB switch device. For my actual setup I still find barrier (forked as input-leap) excellent. I use Linux, Mac, and Windows machines without issue. I even play games with with my input going over the network this way.