First of all, Zhuge Liang in real history is a politician. He doesn't plan on the battlefield like in novels and folklore, so in real history, there is no possibility that Zhuge Liang will unify the Three Kingdoms.

Secondly, the possibility of Zhuge Liang unifying the Three Kingdoms can only exist in the hypothesis of literary works and legends. He has always been portrayed as a positive image of loyal monarch, which is consistent with the real Zhuge Liang who devoted himself to death. Therefore, Zhuge Liang will not rebel whether it is art or historical truth.