What is the maximum input power?
The max input power is 18W. The powerbank is protected with overcharge, overcurrent, overvoltage and overheat technology.
How many devices can you change at once?
You can charge 3 devices at once because there are 2 USB-A outputs and one USB-C output, but when you charge several devices, the total output power will be dropped to 15W shared.
Can you charge the powerbank and charge a device at once?
No, this is not possible.