@Werner-Schreier
This is not a route plan, but a recorded or imported GPX track. In Mapy.com, GPX tracks cannot be edited, reversed, or used directly for navigation.
If this is a recorded track and you want to navigate along it, export it as a GPX file and then use it to convert the track into a route plan as described here.
To reverse the direction, you can either:
first reverse the track using the fast functions on the gpxmapy.cz website before converting it into a route plan, or
convert the track into a route plan in its current direction and then reverse the resulting route plan directly in Mapy.com, as described in the previous post.