nestudoval jsem to, myslel jsem, že to je multiplatformní s google API.
Tady aspoň nějaké kousky:
https://stackoverflow.com/questions/24446949/speech-recognizer-delphi-xe5
https://stackoverflow.com/questions/63835416/target-android-api-29-on-delphi-10-3-3
http://delphi.org/2014/01/every-android-api-for-delphi/
A nějaké obecné:
https://www.developer.com/guides/exploring-the-android-speech-api-for-voice-recognition/
https://developex.com/blog/overview-of-speech-recognition-apis-for-android-platform/