GTrusted

Since the Nintendo Switch Console supports DisplayPort 1.2 over the USB Type-C interface, it theoretically could work with other external displays supporting DisplayPort like the ASUS MB169C+ USB Type-C Portable Monitor. However the Switch Console had problems connecting to the ASUS  MB169C+ USB Type-C Portable Monitor using the USB 3.1 Type-C to Type-C cable that comes with the monitor.

When plugged into the ASUS MB169C+ USB Type-C Portable Monitor, the Nintendo Switch Console was never able to connect or establish screen mirroring with the monitor.

We can also see the USB Power Delivery negotiation between the ASUS MB169C+ USB Type-C Portable Monitor and the Nintendo Switch Console that shows the Console is discovering the identity of DisplayPort monitor and rejecting USB Type-C displays it does not recognize.

Unfortunately the Nintendo Switch Console can't work over DisplayPort with certain USB Type-C displays like the ASUS MB169C+ USB Type-C Portable Monitor.