It seems unlikely as normally a export version is normally simplified, using older more commonly available systems and parts. It might however be possible that in the process of the redesign for the MBT3000 some features or alterations were made from Type 99A2 Causing the PLA to evaluate the possibility of integrating these into the next series of 99 upgrades. It's not Unheard of, For example When Westland Agusta redesigned the Apache for British Service they replaced the GE 700 engines with more powerful Rolls Royce models this added power and although the Us has yet to follow suit there have been arguments to.
The export model of MBT3000 might be different from the version PLA might procure.
If they went through the trouble of doing a major redesign to get to MBT3000, it would not make too much sense to intentionally make the basic chassis inferior to an existing chassis. More likely they would make the best chassis they can, and then add or take away equipment to achieve the level of capability suitable for either domestic or export use.
So MBT3000 might well have a better thassis then type 99A2, but the export version would have inferior equipment fit and power pack than 99A2, but potential exists for the same chassis to receive a better equipment fit and power pack to succeed 99A2.