Strongly recommend this plugin. The formant pitch shifting is pretty much the only way I can get a good femme vocal recording from my testosterone laden cig-y vocal chords. The rest of the Soundtoys collection is pretty fantastic, but replacable. Alterboy is the only plugin I know of that lets you pitch shift the way it does.
Reaper's built in ReaPitch will do formant shifting
And there's Auburn Sounds Graillon, which will do pitch/formant shifting and a lot more besides and has a free version!
I didn't know this, thank you for telling us! Last time I went really researching plug ins was quite a few years ago, so the landscape was a lot different. Graillon sounds pretty damn good, although I could never really get behind Reaper enough to use it :/
I pirate all my plugins so that's why I didn't consider pricing lol
Well if you're pirating them anyway -
I didn't recommend Waves Vocal Bender because their licensing model sucks and they're Israeli; it's the same thing as Alterboy but zero-latency so you can track with it. I actually like it better than Alterboy for that reason