Very Pure and Ambiguous: The Prequel - Volume 3 - Chapter 185: Identical Phones

Ling Xiao was a powerful martial expert who fell in battle and was unexpectedly transmigrated into another world. He began life anew in the body of a boy with the same name, a fallen genius of the Ling Family whose cultivation had been crippled in a surprise attack, and son to a father who had also suspiciously been crippled under similar circumstances. Armed with knowledge from his previous life, Ling Xiao aim to restore his strength and establish his place at the top of this new world

- Description from Novelupdates

Dr Dalton Wyatt, a world renowned Scientist and Inventor is transmigrated to the body of a high school student Dalton Wyatt who committed suicide due to unfortunate circumstances and complicated life.

I just want to be different, no one can guess what I want to do, the more mysterious the more powerful.

- Description from novelbuddy

There are 7 dimensions controlled by a Universal Government. Each dimension is governed by its own unique universal laws. There are a few things they have in common, there is always 1 the strongest and 1 the smartest. Except for the Universal Government, it’s forbidden to travel between dimensions. Interdimensional gates don’t close on their own and if left open, creatures that dwell in the darkness between the worlds will find their way through. Without warning, one of the dimensions disappeared without a trace. The remaining 6 in panic did all they could to find the reason why. They never found an answer. 12 years after the dimension vanished, a signal started appearing in the empty universe. Perhaps the answer is in that signal.Tsugi No Level