The Gemara in Sota which says to teach your daughter Torah is not taking about the Halacha making process. It is talking about knowing Torah. Rashi in Shabbos (31?) describes the Shabbos Drasha as being for the women and Amei Ha’aretz. There they learned Halacha with some rational along with Aggadah.
We only find the issue mentioned as not teaching you’re daughter, which means that it is not an inherent Issur. This is why the Maharil quoted above says that she may learn on her own.