I doubt there will be a void expansion. The problem with the 13th is that there is no civilisation left, and all of the maps would kinda look similar to each other with how they use the areas, having 6 areas that all kinda look the same might end being a big nope for a lot of player. I can see the void being a alliance raid, an exploration zone, or a raid serie, but a full expansion? I have my doubt.