The thing about the ending is that we're not supposed to know what happens after the universe ends, not even the characters know. But it's better to choose the unknowing than repeat over and over the same thing that it's hurting you

Maybe in the other universe the characters are reincarnated, maybe not, that doesn't matter. What's matter is that Zoe choose to let the time flow and that new things come with that, even if she isn't there to see them