mordern: That doesn’t make sense. Lich’ora there shouldn’t be a Mitzvah of Chinuch on Tznius. I think the general assumption is like the Minchas Chinuch and those Achronim who point out that the only Chiyuvim on which Chinuch is Shayach are those that become Chiyuvim at Bar/Bas Mitzvah. Since a girl has a Chiyuv of Tznius before that time (because a girl 11 or younger could be attractive to teenage boys in an inappropriate way) then there shouldn’t be a Chiyuv of Chinuch on it.
