I have trained a text-to-speech engine to synthesize plain tone speech pretty naturally. So now I would like to expand its ability and let it ask people questions, or stress certain words in its answer. However re-train the whole TTS engine with different tones is very hard to implement, as you will need to control the voice actors' tones very carefully, and the current neural engine doesn't do this kind of magic.
So my question is, is it possible that I can use the TTS to synthesize the audio in plain tone, then I use modern DAWs or other tricks to make it into a more suitable speech?
For example from TTS I can get "How are you today", with all 4 words being totally flat and mechanic. Then I may stress the word "How" and lift "you", making it a proper greeting that significantly improves user experience.
Is it possible? If so how could I get started?