They have him as Supervisor and Wikipedia said he was in charge of a team of 17 people who were designing the characters only. All Sugimori did was the final official arts for B/W, and again he was never involved with the actual games outside of drawing the official art for Pokemon and the box art for the main ones. They credit Mana Ibe is all of the games because she works for Gamefreak, but she doesn't directly work on any of the games either.
That was why everyone discredited her statement in the old interview where she said that they were done with the Black and White Installment of the games. Which turned out to be true.
As far as I know Bulbapedia hasn't updated all their info yet.
Trying to beat the game so I can see if his name appears in the credits or not...