Or, here: https://www.aja

Or, here: https://www.aja.com/en/family/kona
This stuff is all very pricey.
If you can’t afford it, I would record individually, transfer files to PC, and use the PluralEyes to sync video based on audio. So, you have to record audio to camera files, to sync up. Then, mute those channels and use your master recording track.