How it does work
Original sentence:
Everyone agrees on how it works.
I would like to know if in the sentence:
Everyone agrees on how it does work.
sounds okay. (In this case, ‘does’ is used to give extra force to the verb work.)
No, "Everyone agrees on how it does work" is not acceptable unless "does" has strong contrastive stress. And, if "does" has contrastive stress, there must be something in the context that explains the contrast. Perhaps someone has indicated that it doesn't work, so that there is the contrast between "doesn't work" and "DOES work".