WHat if in the early 90's instead of supporting the Taliban, Pakistan does what quite a few people in policy position were suggesting and invade with the aim of restoring order in the country, or at least with the aim of pacifying provinces next to Pakistan.
Pakistan had (and still had) two corps in the west ,the XI in Peshawar and the XII in Quetta and could probably provide another, the II from Multan. Thats about 200,000 men in 9 divisions plus corps troops. In addition there are nearly 100,000 FC troops who would (being all Pashtun) would no doubt take part.
Pakistan also had the advantage of knowing the terrain and the people (so many Pashtuns in its own army, including the Army Chief at the time, Kakar), as well as the numbers. OTH, we all know what happened when the Americans went in.