I would like to use Android built-in Google TTS for English and French completely offline. In other words, I not only need to be able to use TTS while the device is offline but also be able to install French voice while offline. My target device is Samsung Galaxy S7 with Android version 7.0. Could someone let me know how to side-load TTS voice data (in my case French) through ADB or something? Basically, the main question is where to download the voice data that matches the version of Google TTS installed on the device and push it using tools such as ADB. Being able to do this installation without having to root the device would be desirable.
Thank you for your help!