I have the 15 inch SB2 so my GPU uses a bit more power than yours, and I have the official Surface Hub which doesn't deliver enough power to game for more than about 90 minutes.

​

Instead I plug in normally, then use a usb-c dock for the following: Ethernet, monitor, mouse, usb microphone, and keyboard. The battery stays charged and I have zero issues with the devices plugged in to the usb-c dock. Here is the dock I use:

https://smile.amazon.com/gp/product/B01N0J5LSY/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

​

I did a fair amount of research before buying that, and at the time Anker did not make one but they do now. So I'd prob get the Anker usb-c hub if I was you