My theories on how the Japanese got there?

Question:

1:ancient xiongnu Tribes who broke away from the confederation
#2:ancient Mongols tribes who wanted to live another lifestyle without persecution
Which one is most likely and your theories.

Answer:

It is true that the Japanese are part of Mongoloid.
But, when you take a close look at Chinese, Koreans and Japanese, you can notice that these three races are extensively different.

It is obvious that the Japanese look more like Mongolians than Han Chinese and Koreans. We don't need scholastic studies on where the Mongoloid was originated from. The same is true with the Caucasians origin.

Obviously, the Japanese are descendants of Mongolians. I am not interested where the Mongolians came from (except for the fact that Homo sapiens were originated in somewhere in east Africa). I am more interested in how the ancestors of the Japanese came from Mongolia to Japan without leaving much blood mixture with the Han Chinese and Koreans. This is a big mystery to me.