The Pokemon Company has announced that Professor Oak (and his cousin, Samson Oak) will now have a new seiyuu, and he is Kenyuu Horiuchi. The announcement comes after the passing of the late seiyuu, Unshou Ishizuka, who passed away due to cancer.
Ishizuka has actually recorded voice lines for Professor Oak and Samson Oak until the first week of October 2018. Horiuchi will be taking over the role afterwards, with his debut as Samson Oak airing on 21st October. Fans might know the seiyuu as the voice of Re:Zero’s Wilhelm Van Astrea, as well as Joker Game’s Lt.Col. Yuuki.
As for the late Ishizuka, he also also appeared in Pokemon the Movie: The Power of Us. And while suffering from cancer and receiving medication, he continued his voice acting work. He has been very dedicated to the role of Oak, as he has been voicing the character since the 1990’s.