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There are a few attempts, I have no idea how good they are. And they're manual transcription only.

There are several open source speech recognition systems (like Deepspeech and CMUSphinx) but there don't seem to be any user-friendly frontends for them.

http://gkarsay.github.io/parlatype/

https://github.com/juanerasmoe/pmTrans

There this python tutorial for it, but you also need ffmpeg: https://pythonbasics.org/transcribe-audio/

Not sure if that helps you or not.

The tutorial itself uses Google, but the library seems to support CMUSphinx. Its documentation seems interesting:

https://cmusphinx.github.io/wiki/

mozilla has open source projects for both speech-to-text and text-to-speech, among other things

https://github.com/mozilla/DeepSpeech

https://voice.mozilla.org/en