From the Google Blog:
Transcribe will be rolling out in the next few days with support for any combination of the following eight languages: English, French, German, Hindi, Portuguese, Russian, Spanish and Thai.
To try the transcribe feature, go to your Translate app on Android, and make sure you have the latest updates from the Play store. Tap on the “Transcribe” icon from the home screen and select the source and target languages from the language dropdown at the top. You can pause or restart transcription by tapping on the mic icon. You also can see the original transcript, change the text size or choose a dark theme in the settings menu.