The history of The Last of Us Part 2 is quite large. Therefore, according to HBO series showrunner Craig Mazin, fitting the entire plot into nine episodes will probably not work.
Recall that the series was officially renewed for a second season on January 27. Release and filming dates have yet to be revealed. The plot of the next season is also unknown.
At the moment, HBO is releasing one episode of the first season on a weekly basis, which is based on the original TLOU, although new details have appeared. The series received high marks from critics and viewers. It currently has an IMDb rating of 9.3 out of 10.