actually, this information must be incorrect. i just bought a ravpower 26800mah usb C PD powerbank that came with a small usb-c charger and both support 20V/1,5A via usb C. and only the wall-charger can charge the acer via its usb-c port. the powerbank doesnt (annyoingly). where as i read now in another amazon review that an acer switch alpha 12 actually does charge with this powerbank!
so something in this acer r7-372t keeps it from doing the same, some missing firmware update or possibly different hardware. but at least it charges from this little wallcharger from ravpower at about 23Watts. I can confirm that!
seems not even the manufacturers can see thru the usb-c mess! sad very sad :-(