Chiefs Rugby Club chief executive Simon Graafhuis said Stevenson had been a special part of the club for nearly a decade.
“Not just for his talent on the field, but for the character and energy he brings off it.
“He’ll always be part of our Chiefs whānau and I look forward to seeing him shine in Japan.”
The news comes after Stevenson sought an immediate release from his New Zealand Rugby (NZR) and Chiefs contract in December last year to take up a deal with Kubota.
NZR was hesitant to grant Stevenson’s request so close to the start of the Super Rugby Pacific season, due to the precedent it would set for other players wanting to move abroad.
His contract expires at the end of the 2025 season.
Ahead of this year’s Super Rugby season, Stevenson was granted a short-term sabbatical from his NZR deal to start this year in Japan.
Due to this, he was unavailable for the Chiefs’ matches against the Blues and the Crusaders in February and against the Brumbies in March.
Stevenson, originally from Auckland, started his provincial campaign with Waikato, before moving to North Harbour in 2017.
For North Harbour, he reached 70 caps and scored 27 tries.
North Harbour Rugby paid tribute to Stevenson on social media.
“North Harbour Rugby bid farewell to a true champion of the Union, @shaunstevenson_
“He’ll be warmly remembered for his love of the community game and growing the next generation. Thank you Shooter and all the best for your return to Japan.”
Stevenson has also represented the Māori All Blacks in their 2018 and 2019 campaigns and was selected again in 2021 for their two-game series.
After an outstanding 2023 Super Rugby Pacific season where he played every game, scoring 12 tries, Stevenson was named in the All Blacks squad as an injury replacement for the Lipovitan-D Rugby Championship.
He made his only test appearance for the All Blacks, where he scored a try against the Wallabies during the Bledisloe Cup 2023.