Some time ago I posted a question in the Quest for Glory question about who would play an EGA version of Quest for Glory 5. So perhaps that might count?
Of course, I could wonder how an EGA version of King's Quest 8, which (to my understanding) is very different from the rest of the series, might work.
One strange idea I've had, which could qualify as a demake by some definition, would be an idea for a Final Fantasy 7 remake. The catch is, however, that the remake would not be an RPG (even by permissive definitions); it would be a linear sidescroller much like classic Castlevania games. You would have mechanics like only being able to carry one materia at a time (press Up+B to cast the spell, but each materia has limited uses), Potions work immediately (can't save them for later), and Phoenix Downs would act as 1-ups. Think that might be an interesting game, even if it would not resemble the original gameplay-wise. (Incidentally, part of the game has been demade by fans; I saw a Youtube video in which the initial reactor mission was playable. Said demake was an RPG, unlike the idea I present here.)