"Fantastic Beasts 4" is confirmed, but beyond continuing to follow the adventures of Newt, exact details surrounding its plot have yet to be revealed.
While speaking at a Warner Bros. fan event in Japan, the franchise's producer, David Heyman, revealed the film is still in its early stages. When asked if the Fantastic Beasts movies would ever take place in Japan, Heyman said, "We haven't yet started writing the next film, so we'll have to see. If I have my way, we'll definitely be going to Japan," according to The Rowling Library.
Considering the script hasn't even been written yet, it's likely the movie won't premiere for another couple years at least.