There is not much power needed to receive DisplayPort over USB (assuming you already can receive displayport signals or just route them to an external monitor).
You just need to implement an USB billboard device (optional to make it work, but required by the spec IIRC) and signal the correct alternate function. Then DisplayPort signalling will be present on the USB-C plug. Then just connect the right AUX wires to the DisplayPort connector.
You just need to implement an USB billboard device (optional to make it work, but required by the spec IIRC) and signal the correct alternate function. Then DisplayPort signalling will be present on the USB-C plug. Then just connect the right AUX wires to the DisplayPort connector.