Which is the last software version of the fenix 5 plus? I have the 13.0 version but my brother has a fenix 5x wiht 20.0.
That is correct, 5x is previous generation before yours, so it has higher version. Your version 13 is right, more details in your forum for 5 plus: https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-5-plus-series
