I’d be interested in a version of this that guesses regional American accent backgrounds. I’d like to think it would have a hard time with me.
Nice suggestion! BoldVoice focuses on helping non-native English speakers to learn the American accent, so we tailored the accent oracle to non-native accents specifically.
That said, if you want to teach people to speak with an “American accent”, you should probably be aware that there is no “American accent”, only regional accents.