How to change the language on Strava (iPhone)
First you and will have to add a new language to your iPhone. (This is necessary first to be able to change the language on Strava from one language to another).
navigate to Settings > General > Language & Region > Add Language
Add english (or what you prefer)
When you have done this, you can change the language on Strava.
navigate to Settings > Strava
Now you will have the option «Preferred language» in the bottom of the settings. Then you can change to english, or the language you have added on your phone.
Hope this helps!
I also hope Strava will add the option to change the language directly in the app…