Judgment will get a sequel sooner or later, I'd guess they just want to have it available on current gen systems fast to get ready for that.
Same reason they need to port Sakura Wars fast, as it was planned as the first of many with the new cast(gama sold well in Japan at least).
About Stadia.. it's a money hat, according to a insider, they are paying to keep it from Steam for a while, very likely a old deal as I doubt they would go that far after today's announcement.