Bguy7
The Dragon Lord
The logos alone make it pretty clear that the sun pokemon and the moon pokemon are sticking with their respective titles. But anything is possible.
It's possible, but it's such a small chance that it's really not even worth speculating about.
Unless something changes, I'd say get the opposite version you got before. With B2W2, the benefits to getting the same version's sequel was carrying some of the plot elements over and getting the other legendary, with USUM we're not sure whether the story is being advanced or not and we're keeping the same legendary to their particular version, so both of those perks aren't present. Plus, other version exclusives could be retained as well, so if you want to catch them all without WiFi or trading with other players you can get access to all of the Pokémon through both games. So there's more benefits to switching it up here then there were with B2W2, at least at this point in time.
This is just my opinion. but I pick my game solely on the cover Legendary, so I'll be sticking with Ultra Moon. Even back with Gen V, I first played White Version, then Black 2. There was no way I was going to get Reshiram instead of Zekrom, especially with how awesome Black Kyurem was.