The driver will recognize that there are two MOXFs connected and designate one as "1-MOXF6/MOXF8" and the other as "2-MOXF6/MOXF8".
Each will have its own 5 MIDI Ports, and depending on the type of computer* you have, each MOXF will have the ability to output 4 Channels of audio.

*If Mac you can build an Aggregate Audio Device that handles all the USB audio ins simultaneously. Connect the audio out of one to the A/D Input of the other for direct monitoring purposes.
*If a Windows PC, you designate one as the audio interface and connect the other to the A/D inputs for direct monitoring purposes.
In both instances: Only one MOXF need be connected to your speakers.
Professional DAWs like Cubase allow you to "hot swap" audio interfaces, this means you don't even have close the Project or turn anything off or reboot anything... just click, click, done.

Each will have its own discreet communication path to its own Editor, again, one will be designated "1" and the other "2".

At maximum (in theory) you could connect 16 MOXFs... anybody trying this (connecting 16) let me know, I've never had cause 🙂

If you run into any issues, post back here.

Thank you for this precise answer.