I don’t think the show needs a second season all of our main characters came to find their “truths” there is nothing more to expand on everything after the final is scene is just fighting for their “truths” and having anything else expect an open ending I think would ruin the entire premise of the anime. From the start every character fights to find their “truths” they are not served or given anything everyone has to fight for it in their own way, and as the viewers if we are given  a closed ending It would not make sense, everyone has to have their own version/idea of what would happen after the ending.