Bandai Namco announced via their Twitter account that Doraemon: Story of Seasons will release for Nintendo Switch and PC worldwide on October 11, sticking to the planned Fall 2019 window. A physical release has been reported for Europe, while the title appears to be digital-only in North America. Additional details on the concurrent PC release via Steam are still mostly pending.
Doraemon: Story of Seasons released in Japan for Nintendo Switch on June 13. You can view the original localization announcement and trailer here, and read our summary of a Famitsu interview with the game's producer here.