There are in total 4 interview rounds.
The first is a typical Python coding test where you have to solve three (easy - medium) Leetcode questions.
The second is a Machine Learning specific interview, where you are asked basic questions regarding (modern) Machine Learning, i.e. Gradient Descent, Neural Networks, Optimizer etc. For that the interviewer discusses a take-home assignment that you have to submit prior to the interviews.
The third is a 30-minute presentation of a recent AI paper of your choice. Afterwards, there is a discussion with the audience where you have to answer questions. The questions might also be somewhat unrelated to the presentation itself.
The fourth is directly after the presentation, which is a short "culture screen". After the interviewer explains a little bit in more detail what the company does, he asks for your desired wage, your desired location (Japan/Abroad), whether you need sponsoring etc. In the end he also asks a question regarding your personality.