Voice shifter plug-in

This plug-in already exists and it's called RoVee, a very simple and free plug-in made to shift the timbre and pitch of the voice. This plug-in needs a shifting audio update because it has so many artifacts/robotic sounds that makes voice not sound natural at all. This plug-in has no quality audio loss like other programs/plug-ins made for this Basically all i want is something exactly like this plug-in but without artifacts Please reply, price is negotiable and it also can be pay fixed