Maybe the Overcharge ocucured when i set the Voltage to Level 6 (There wasn't a Level 5, only 4.5 and 6)
pero. no lo conectaste directo, usaste el HUB?
This is quite late, but the Mi Stick does not support OTG + Charging like the Amazon Fire Stick / MeCool KM1 stick does.
I have all three, and tested them using the Micro USB/USB splitter, and the Mi Stick just totally won't recognise any external device
Have you tried the stick without the hub? If it still don't work, then yes... You probably fried it with that power supply. Did you checked the voltage polarity before plugging it in? Also, the nominal voltage in those old bricks is higher than stated expecting a voltage drop under load.