Theoretically, it is possible. But it's hard to do. In general, professors in the relatively popular research rooms of good universities are eager to have face-to-face communication with students, but rarely can they guarantee that international students have a visa to meet. So if you don't apply for Japanese graduate students (that kind of preparatory course), I'm afraid it's unlikely to enter the research room of your favorite university.

Of course, research professors sometimes go abroad for exchanges. If they happen to come to China for a meeting and exchange, they don't have to go to Japan for a meeting alone. But the probability of this happening is not high.

Anyway, if you want to enter the university directly, you should apply for some unpopular professional research rooms of non-famous universities, or apply for tutors as associate professors, so it is more likely to enter the university directly.