The mapping of ISIS and it's affiliate groups is complex and challenging since the organisation can be broken down into Zarqawi’s Reign (October 2002-June 2006) the decline (2006-2011) and subsequently the Expansion under Baghdadi (January 2012-Present).
At present ISIS is affiliated with 43 terrorist organisations around the globe.
With that caveat in mind it's best to focus purely on ISIS and their own guidance rather than the affiliates which are amorphous, fluid and changeable with no true C3 infrastructure.
At the beginning of 2015, ISIS published a guideline for women under the title Women of the Islamic State: Manifesto and Case study. The manifesto was published in Arabic on various online Jihadi forums. It was translated by the British think tank the Quillam Foundation, a counter-terrorism organisation, and provides an insight into the lives of women within ISIS.
The manifesto was drafted by the al-Khansaa Brigade, a female-militia setup of ISIS, largely comprising educated Western women. It operates as an ultra-oppressive police force, monitoring females. This police force imposes punishments on anyone who does not follow the strict guidelines of behaviour for women in this society. Enforceable rules include the requirement that all females dress only in black, including their shoes, cover every inch of their bodies, and wear gloves to cover their hands and fingers.
One of the leading figures in the al-Khansaa brigade is 20-year-old British girl Aqsa Mahmood. She was reported missing by her parents before surfacing in Syria, and has become one of the main female figures of ISIS through her social media activity.
The translated version of the document—which including the analysis is 41 pages long—extols the virtues of motherhood and promulgates the idea that the best place for a woman is in the house, living a life of "sedentariness" and fulfilling her "divine duty of motherhood." It portrays Western civilization as a godless, materialistic society that has caused women to depart from their God-given roles as wives and mothers.
It doesn’t put women on "equal" footing with men because the two sexes have distinctly different roles under Islam: "Women gain nothing from the idea of their equality with men apart from thorns," the manifesto states. "Under 'equality' they have to work and rest on the same days as men even though they have ‘monthly complications’ and pregnancies and so on, in spite of the nature of her life and responsibilities to their husband, sons and religion."
In 2014 there were an estimated 550 Western women fighting for ISIS either directly or indirectly according to various intelligence agencies from the 5 EYES community.
Research in this Area
Katharina Kneip has published a report specifically on Western women fighting for ISIS which can be found on the IAPSS Political Science Journal
Important contributions have also been made by Erin Marie Saltman and Melanie Smith who published a report in May 2015 (Saltman and Smith 2015) for the Women and Extremism (WaE)project of the Institute of Strategic Dialogue (ISD) following a primary report launched in January the same year.
Yes, ISIS do in fact have many female fighters however their role in fighting either directly or indirectly is largely intimidation and control of other females.
If you are interested in wider female involvement in Jihad or Qutb-inspired fighting you might find the Mother of Martyrs interesting. Mariam Farhat celebrated her sons dying in the name of jihad.
"jihad comes ahead of everything, including my feelings as a mother."