Doesn't the Anker wireless charger come with a power cube? How much V and A does it have? I would think you could use a 12W USB-A charger with a normal microUSB cable.
My Samsung Wireless Quick Chargers come with cube that says "9v-1.67A or 5v-2A" (10-15W) with a USB-A port, and it uses a normal USB-A to USB-micro cable. With iOS 11.1.2 my iPhone X charges about as fast as the 5W cube that came with the phone. The box claims the charger can go up to 9W quick charge (vs 5W for normal).
My 30W Anker USB-C charge cube is for Wired Quick Charging. I only use it with a USB-C to Lightning cable from Apple. I went from 10% to 85% in just an hour with it once. I'd worry the 30W Anker USB-C to Micro-USB would overheat or fry the Wireless Charger, unless said charger is smart enough to only draw what it needs.
My 12W iPad charging cube with USB-A to lightning cable will get past 60% in the same amount of time, and to 100% in well under 2 hours. I suspect that same 12W iPad cube could also power the wireless charger with a standard micro-USB cable, but it wouldn't be any faster than the one that came with my Samsung charger.
