I've reviewed the documentation, and wish to confirm what i understand as being a valid application:
MacBook Pro (15,3) connected via ethernet adapter, running Cubase Pro 10.5 or GarageBand, communicating with Yamaha DGX-650 (USB MIDI,) a couple of Korgs (DIN MIDI) including THRU of MIDI clock, SPP and note data to E-mu MP7.
I suppose my only question is the Yamaha USB MIDI port, as i've only had occasion to connect to Mac host, so i'm assuming there's a standard implementation for USB MIDI that Yamaha has followed with their digital grand.
I'm not sure. It looks like there are drivers that need to be downloaded to use the Yamah DGX-640 with Windows so maybe it os not Class Compliant. I didn't see anything in the manual that indicates that either way.
It doesn't seem to have a MIDI DIN connector either. Here is the link to the manual. You should probably check with Yamaha to see if it is MIDI USB Class Compliant.