Continuing to take photos with a battery pack hanging off a device is no where near as simple as popping in a fresh 100% battery and coninuing as normal.
just to note, wireless charging is very inefficient. From the page you linked:
"Due to a 30% to 45% energy loss in battery cells and conversion circuitry, a fully charged 5,000 mAh power bank typically offers an estimated 2,750 to 3,500mAh to power devices"