I Am Legend 2 will follow the alternate ending of its predecessor film instead of the theatrical version and there are some steps it can take to avoid confusion. The news that I Am Legend will receive a sequel 16 years after its initial release has been exciting news for many. However, the information that the film would bring back lead actor Will Smith – whose character died at the film's conclusion – inspired some questions. Film writer and producer Akiva Goldsman cleared this up by clarifying that the film is sticking with the original movie's alternate ending. However, it still leaves several obstacles in I Am Legend 2's way.
https://screenrant.com/i-am-legend-2-alternate-ending-confusion-prevent/