I'd suggest taking a look at the USB-C Power Delivery spec.
I tried to get it to just deliver 5V to the bus (info here: www.tangiblewaves.com/diy-info.html ), but found it wasn't stable enough (even with a laptop power supply regulated down)
Unsure why this wasnt clean enough but decided in the end to just output 9V - then just a cable to patch the power from my module to the Master and bam - can power from a USB-C power bank. Added benefit of being able to daisy chain to any other 9v synth like a volca all from one plug (or pedals if using the right polarity adapter), running it through one of those laptop hubs too and can power USB-A devices too
Excuse the shoddy center positive symbol - should have drawn it before adding the components in.