I always wanted to have a text-to-speech system that could generate novel accents, by taking just a couple parts of the IPA at a time and substituting other sou

I always wanted to have a text-to-speech system that could generate novel accents, by taking just a couple parts of the IPA at a time and substituting other sounds. Text-to-IPA might be easy enough with dictionaries, the swapping is trivial, but IPA-to-speech seems like a harder problem.