F-Droid?

"Simply" isn't so simple here. If that were possible I could replace my banking app with one of the same name from F-Droid, which would enable me to extract my login data or whatever, which shouldn't be possible without root. Well, if you already have root you don't need all these shenanigans anyway.

Alternately if replacing the app with a differently-signed one destroys the data, then you could just as well deploy the new app under a different name and avoid all that hassle.