There's no way to connect a display over DisplayPort (to get 4K@60Hz, whereas all the abundant HDMI-having docks/adapters/hubs would operate at HDMI 1.4 limiting to 4k@30Hz) while charging the laptop at the same time.
Looking for a product that supplies passthrough power while NOT converting to an HDMI signal.
Best Answer
Usb type c to display port adaptors with 4k 60Hz resolution are available on the market.
In order to get a 4k 60Hz resolution output on the display port side your usb-c port must support Display Port alt mode. Laptops that have this type of usb-c ports are MacBook, ChromeBook Pixel™ and Dell™ XPS™ models 15 and 13. When the usb-c port does not support the Display Port Alt mode then the max resolution is limited (mostly to 1080p) regardless of an extra power supply for the adaptor.