If you want to hear a different voice for your voice announcements on your Android device, proceed as follows:
Download a TTS app of your choice from the Google Play Store. (For example, search for "TTS Voice English")
Then change the language in the settings. (Profile (Header Icon) -> Settings (Gear Icon) -> App Settings -> Navigation -> Install Language)
Set here the standard module for speech synthesis
To be on the safe side, check the language again (Profile (Header icon) -> Settings (Gear icon) -> App Settings -> Navigation -> Check voice output)
Also check in the Modules section of the Text-toSpeech HQ entry whether the selected app is really set.