It's the TESmart KVM Switch... HDMI 4K 60hz 4:4:4, I like it okay. Seemed about the best option on Amazon, but mixed reviews. My display is 60hz, and I don't play many games, so it works well enough for my use.

I did get hdmi adapters for my pi4's, but haven't actually tried them yet. May need different adapters/cables if you're going to/from mini-dp or another interface. back of the switch looks like USB-B Female (standard USB cable, not 3) and HDMI Female.

I've only been using it for about 4 weeks, but so far working well.

KVM (comes with 2 cable sets): https://www.amazon.com/gp/product/B07F6XFVZ3/

Extra 2 cable sets: https://www.amazon.com/gp/product/B075FRFXNX/

Micro HDMI to HDMI (for pi4): https://www.amazon.com/gp/product/B00JDRHQ58/