I have played with this device and got CircuitPython working on it. It’s fairly undocumented but with the demo apps source I could get the touch, accel, and screen working. However I’ve not been able to get the battery to last more than an hour even with screen blanking.
I saw that waveshare link and was really hoping for some eInk stuff. I would buy a package like that in a heartbeat if it had eInk. Heck, might even get a couple if the price was right.