With the release of Mario & Sonic at the Rio 2016 Olympic Games on 3DS in Japan, we now know the new Japanese voice of Eggman to be Motomu Kiyokawa.
Motomu Kiyokama succeeds the late Chikao Ohtsuka, who voiced Eggman from Sonic Adventure 1 all the way to the Sonic Boom games. Chikao Ohtsuka sadly passed away on January 15th, 2015 due to a Ischemic Heart Disorder.
Among Motomu Kiyokama’s Japanese voice acting credits include Thomas in the 90’s Virtua Fighter TV show, as well as the Mahogany Town Gym Leader Pryce (from Gold and Silver) in the Pokémon anime.
The news of the new voice actor came from our own Tracker on our forum, and we even have a clip from a Vine account by a user with a copy of the game which you can view here (make sure to enable sound).
Thanks go to both for the news.
Image (along with many more voice acting credits) via Anime News Network.