This is exactly the expression I evaluated on a newly rebooted machine, the only difference is I told it to display as a table using the //Dataset function. No previous lines are executed. My version is 14.1.0.0, Windows version. Nothing else was modified from a "normal" install.

In Windows 10 or 11 go to Settings and search for Voice. Really looking for the Speech settings.

Choose "+ Add voices" from "Manage voices" Load the German (Germany) voice package

After loading voice files or files, and from a fresh Mathematica kernel run (not install)

VoiceStyleData[] // Dataset

You should get at least for German (Germany)

Female German Hedda

added to list

The default for VoiceStyleData[] is Automatic which is what your system supports

Thanks Hans! This worked and I got Hedda to speak! However, I cannot imagine that all 52 languages from the documentation need to be installed this way, including other voices for German itself. Knowing Mathematica, there has to be a better way.