Is trousers specific to men, and is it forbidden for women to wear them? And are there any clothes or things that were specific to men and then became permissible for everyone?

Wearing trousers by a woman outside her home or in front of non-mahram men is forbidden (haram) because it does not cover her 'awrah (intimate parts) and reveals her charms, thus contradicting the prescribed Islamic covering and resembling the attire of disbelieving women. However, there is no objection to wearing them at home in front of her husband or mahrams (with reservation in front of mahrams) or underneath a jilbab. The blameworthy imitation (tashabbuh) is that which is exclusive to one gender or to disbelievers. This changes with the alteration of time, place, and customs; so, what was once exclusive to them but then became widespread among Muslims is no longer considered forbidden imitation. The objective of Islamic dress for women is modesty, dignity, and concealment, and to avoid displaying adornments and charms.