The Al-Khalid and the Altay are of completely different designs. The former is a typical Eastern (Soviet-Sino) design.
The Altay is more in line with typical Western designs like the Leopard, Merkava, Abrams, etc. When I say Eastern, that is not including Korean tanks, which are more Western-like.
In fact, the Americans did offer Pakistan the M1 Abrams sometime back in the late 80s. Pakistan rejected it after some tests. It was way too heavy.
So, they worked on their own with Chinese assistance. The result: Al-Khalid and a very capable tank.