So this was a thought that had rolled into my mind a while back. After watching Persia/Pelsia I became interested in the "Wild Child" type of character. The kind who climbs trees, mingling with animals and having a hard time grasping the basic concept of normal human life.
I happen to have an OC who fits these qualifications and considered doing a cute witch style story with her. The problem? She does not speak a word. At best she makes cute little noises.
"Ah?"
"Ooh!"
"Ehe~"
And so on. It made me wonder how that would work in a genre that is built upon stock phrases and incantations and calling your attacks. As I mentioned in the Pelsia thread, when she changes into a toddler she has a difficult time turning back due to her downgraded speech skills.
So I wonder how it would work if a Magical Girl was completely incapable of speech on a normal level. I guess there's no reason an incantation is necessary, but I can't think of a single traditional magical girl show that doesn't requite at least something like "Precure! Smile Charge!", and it specifically mentioned that the character NEEDS to call out this phrase.
A lot of old timey magical girls transform into older forms, so maybe her older self would be able to speak.