Need Help With a Keystroke

Mac OS 10.14.6 running version 9 of KM.

I've added a piece of software named Across ( that is essentially a KVM bluetooth app. The hotkey command to switch keyboard and mouse between computers has four options in the Across menu: left and right control, command, option or shift (i.e. pressing both the left and right of each key at same time). I haven't been able to figure out how to get KM to do that yet. Any ideas?

Does a device key trigger (as opposed to hot key trigger) differentiate between them?