Well if they conquer Egypt there are the obvious short term consequences such as no Mamelukes. After a while they will most likely convert to Islam (Or maybe even become Coptic, THAT would be an awesome idea for a TL).
They then pretty much ride unchallenged till they reach Morocco and face the Maranids, and if they succeed they will continue on to Iberia, if they are Muslim they will continue the fight against the Reconquista. ( At this point in time, besides Granada, Muslim presence had near enough died)
After there is completely up in the air, they could fail against the Iberians, restore Al-Andalus to its former glory, the possibilities are endless.
These are just my thoughts, I once thought about this idea when I heard about the Battle of Ain Jalut. (By the way I did think about making a TL about this, and maybe I will return to the idea).