I managed to solve it. When I load the project in Nuendo, there was a second pause before it hangs. So I tried to load this project again in nuendo and once it load I immediately press arrow keys on my keyboard (qwerty) to navigate the track. then it didn’t hang. PHEW!
Now I looked manually what has same names and renamed them. I mostly name all my tracks but in the hectic work flow with some projects, I load a vst instrument and dont rename, so eventually I ended up having 3-4 tracks that were same vst instrument name. If they were loaded in order below each other, then they add an incremental numbers for new tracks. But if I navigate to drum section tracks and added new vst instrument track, it won’t add any incremental number.
It would be great if Cubase can automatically add numbers at end when it finds there is another track with same name.