Translate / replace line chart label expression

Hi

I have a Line Chart, works as expected but I would like to translate the weekdays to german. To be able to group them I’ve a property where I store the weekname. When outputting I would like to see the german weekday names.
Finally I would like to have the app multilingual.

To get my task done, I tried with a string replacement but I couldn’t replace multiple strings and probably there’s a much more elegant way.

I add some screens to showcase where I’m stuck.

Any advice is appreciated. Thank you.
Best, Jacques

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