Hi @Eberl Sebastian Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
As per the documentation on Migrate .NET apps from the in-process model to the isolated worker model, there is no indication that the function app keys would change.
However, if you do find the need to update or create a new set of function app/function keys, you can do so by following either of the approaches mentioned in the article Renew of create access keys.
Hope this helps! Please let us know if you have any additional questions or need further assistance.
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