Is it permissible to study for a master's degree at a women's university affiliated with the Catholic Church abroad, given that there is no compulsion to study religious subjects?

It is permissible to learn from non-Muslims what a Muslim needs for their worldly affairs, provided one is fortified with the correct creed, lest some of their misguided beliefs seep in. So, if you are fortified with the correct creed, there is no harm in studying at their universities, while keeping in mind to despise the polytheists and disavow them, and to be keen on demonstrating the rituals of the religion and not compromising any part of the Sharia to conform with them.