My tip would be to buy enough hmdi leads, so that each telly has one (for the firestick), and leave them plugged into each telly.
Logic being:
- saves you having to firk around the back or side of each telly, every time you want to plug the firestick in
- repeated plugging / unplugging of the stick directly into the telly runs the risk (however unlikely) of damaging its hdmi port.
By using the hdmi lead as a sacrificial part, this negates that risk.
I'd rather risk (and replace) a cheap hdmi lead, than a telly.