I agree with red dragon its pointless to be arguing things from a game and try to analyse it to the canon manga. The Naruto/Hinata its fan service to please the fandom and have more sales (especially in the west since NH is famous there). We shouldn't even be comparing things from the game to the manga we'll be no better than the NH fandom who relies on a video game to prove their pairing will happen. Fans like VJ87G will buy the game and when he does the Naruto/Hinata combo move he will scream "this makes NH canon period!" then he'll make a video all about saying Ninja storm revolution is the only reliable source to show that NH will happen bla bla bla. When the reality is that the western fandom along with him will use the game to defend their pairing. A game Kishimoto has NOTHING to do about it (with exception of designing mecha Naruto), a game that is not considered canon manga material (except for the canon story obviously). So lets forget about the game let the fandom use it for pairing evidence.
I think I heard that Kishi also wrote the special stories in the game, the ones that take place in the past.
- The creation of Akatsuki
- Itachi and Shisui
- Kushina with Team Minato
Dunno about the one with Mecha-Naruto, maybe he did that too. At the very least he did the design like you said.