I don’t have a straight answer … but what about Strava do you like?
The line you see on Strava (or any fitness tracker) is just a trace (log) of where and when you went. That can be exported into many formats and moved between many different viewers. There is nothing special about Strava’s GPS trace.
Recording that trace can be done with different things, software or devices. Then importing that trace into different places can be done.
If it’s the social features you like, then that would be a different focus and might influence what apps you might want to consider. Komoot is a germany based company that does this really well.
Fitness tracking? Again, that can be a focus. Runalyze seems to be winning out in this space and is based out of Germany.
Where are you based? Some apps are more focussed on one country than another.
OSMaps
Take a look at runalyze . The analysis features are imo second to none. Once you get over the learning curve