What about one MQS with one ethernet port for POE IN and another ethernet port for POE OUT. The new ethernet port will be only used to get power from the current wire, and also can be good for do not have the device down so much time while configuring it.
It will be easier to disconect the Mikrotik device ethernet cable, connect it to the MQS2 (new device name) and add another ethernet cable from the MQS2 to the Mikrotik device. We won't need the the USB Power Bank, and we get rid about problems of out of battery on the Power Bank.
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