User blog comment:Teridax122/What to call the Ultra Series universes/@comment-33069649-20171109005259/@comment-5527544-20171109164451

To answer these questions...

X, Orb and Geed, take place in their own universes. How do we know...? Because in each of those series, the idea of an 'Ultraman' is new when the titular Ultra first appears. This means none of these series follow the history of the Showa Universe, like Mebius did, when Mebius first appeared on Earth, there was immediate recognition to what he was.

Zero, and Belial are from the Showa Universe, and the Multiverse is just a means of keeping the previous lore, but without the immediate consequences (like a wrecked Japan....)