One solution I've found is this: the iOS app Voice Dream allows you to take highlights and notes while listening to an epub file being spoken by your choice of

One solution I've found is this: the iOS app Voice Dream allows you to take highlights and notes while listening to an epub file being spoken by your choice of voice. Then you can export the annotations as a text file in this format: CHAPTER NAME (percentage of the way through the text)% HIGHLIGHTED TEXT OR NOTE I find it suits my use case.