On 10 January 2019, Watanabe was announced at Azul Claro Numazu from the 2019 season.
[1] Whilst at Azul Claro Numazu, he worked as a hotel receptionist and at a car dealership, but after transferring to Fujieda, he was able to focus solely on football.
[2] Watanabe made his league debut against Cerezo Osaka U-23 on 10 March 2019.
[10] On 29 July 2024, Watanabe was announced at Júbilo Iwata on a six month loan deal.
[13] On 5 January 2025, Watanabe was announced at Júbilo Iwata on a permanent transfer.