YI have nothing against Chinese internal training, but I didn't know ,that is, what IT meant.
It's not just Chinese
internal training. Some Japanese people who have IT and got it from (mostly) Japanese sources: Morihei Ueshiba, Sokaku Takeda, Yukiyoshi Sagawa, Tetsuzan Kuroda, Minoru Akuzawa.
Reading recommendation in this regard: Hidden in Plain Sight by Ellis Amdur.