Why would the Heter of Mitoch work for a woman? When you are Mechuyav to learn, Lishma, you should do whatever you could to get there, even if it means learning Shelo Lihma. But if you don’t have that Chiyuv then it’s not Nitan Lidachos.
But, going with the famous Tosafos Pshat that the Shelo Lishma of Noach Lo Shelo Nivra is not the same Shelo Lishma of Leolam Yilmod, there is no Issur in the first place.