Since congregational prayers are obligatory on men and not on women, the mosque naturally becomes a place where men primarily congregate, so a women’s only mosque is unnecessary. The Holy Prophetsas said:
Do not prevent your women from visiting the mosque; but their houses are better for them (for praying).
(Sunan Abi Dawud, Book 2, Hadith 567)
Also, the Holy Prophetsas said:
The Friday prayer in congregation is a necessary duty for every Muslim, with four exceptions; a slave, a woman, a child, and a sick person.
(Sunan Abi Dawud, Book 3, Hadith 1,062)
Friday prayer is mandatory upon every mature Muslim. However, it is not obligatory upon those who are sick or traveling; it is also not obligatory upon women. However, if they participate it is fine, otherwise, they should observe Zuhar prayer (Fiqh Ahmadiyya, vol. 1, p. 161).
An answer to the question of whether it is permissible for women to observe a separate Jum‘a Prayer:
We do not find any example during the time of the Holy Prophetsas and his Khulafa’ of women having observed a separate Jum‘a or Eid, it is also the sunnah that men and women gather in one place and observe Jum‘a or Eid. However, since women can observe separate congregational prayer when needed, therefore in principle there does not seem to be any wrong in their sometimes observing a separate Jum‘a or Eid when needed with the permission of markaz, with the condition that it not be made a regular habit.
(Fiqh Ahmadiyya, vol. 1, p. 169)