Before Gainax was founded under the official name, Yoshiyuki served as animator on the second animated project, the Daicon IV opening animation. His first assignment as a character designer in Gainax was for , released in 1987. Sadamoto has since had many works credited to him, one of the most notable being Neon Genesis Evangelion where he worked as a designer for the characters. Yoshiyuki's three most recent films include: The Girl Who Leapt Through Time, Summer Wars, and Wolf Children for which he was the character designer. According to Yasuo Otsuka, who guided Sadamoto as a newcomer, there are only three people whom he regarded as more skillful than himself that he has met during his career. One of them is Yoshiyuki Sadamoto. The other two are Sadao Tsukioka who became a visual creator, and award-winning director Hayao Miyazaki. When Otsuka met the three men, he seems to have felt that he was taking off his hat to them at once. However, he thinks that only Miyazaki completely mastered a genuinely superior animation technique at present. He guesses, "A too excellent person might despair in the group work". During an interview with Japanese Entertainment website Nihongogo done in 2013, it was revealed that Sadamoto is a stickler for details and wouldn't feel comfortable illustrating anything too unfamiliar to him. "In general, I don’t want todraw something that I have to study further in order to draw. For example, I could not draw a medical manga because it’s impossible for me to make a lie about medicine. Also things like Soccer and Baseball. I am unfamiliar with these worlds so it would be too difficult to show the actual plays." When asked about dream collaborations he revealed an interest in working with Robert Westall and Philip K. Dick but apologized "These are all deceased people, sorry."
Controversy
On August 9, 2019, Sadamoto received criticism for his comments on Statue of Peace, a statue by Kim Seo-kyung and Kim Eun-sang depicting a comfort woman. Sadamoto claimed it was propaganda as he called the statue "dirty" and "vulgar". His comments have been viewed as offensive and nationalistic.
