Most anyone who's used noise-canceling headphones knows that hearing the right noise at the right time can be vital. Someone might want to erase car horns when working indoors, but not when walking along busy streets. Yet people can't choose what sounds their headphones cancel.
Have the headphones convert the conversation to text then have the headphones read back the text in the voice of the speaker. And you could give them a southern drawl.
Have headphones and AR glasses working together to give people subtitles