Women are permitted to combine and shorten shalat during Haji in exactly the same manner as men. There is no distinction between men and women regarding the concessions of combining (jam) and shortening (qasr) shalat during travel and at the specific Haji sites. All scholars agree that the rulings of combining shalat at Arafah and Muzdalifah apply equally to women.
At Arafah, all jamaah haji — men and women — combine Dhuhr and Asr shalat at the time of Dhuhr (jam taqdim), shortening each to two rak'ahs. At Muzdalifah, they combine Maghrib and Isha at the time of Isha (jam ta'khir), with Isha shortened to two rak'ahs. Sheikh Ibn Baz confirmed that these concessions are Sunnah and apply to every jamaah haji regardless of gender.
Sheikh Ibn Uthaymeen further clarified that women who are traveling for Haji may shorten the four-rak'ah shalat (Dhuhr, Asr, and Isha) to two rak'ahs throughout their journey, just as male travelers do. The shortening applies when they are considered travelers, and the combining applies at the specific Haji locations as part of the Sunnah of Nabi. Women who are residents of Mekkah shorten at Arafah and Muzdalifah due to the Sunnah of the rite, not due to travel.