[4] In the Summer of 2019, Sato progressed to the FIA Formula 2 Championship, replacing Arjun Maini at Campos Racing from the round at Spa-Francorchamps onwards.

However, after the fatal accident of Anthoine Hubert,[5] the Japanese racer would not officially make his F2 debut until the Monza feature face, finishing twelfth overall.

[9] A point-less opening weekend in Bahrain was followed up by his first points finish of the year, as Sato ended up eighth in the sprint race at Jeddah, after which he praised the team for the strong pace.

[11] The following rounds brought with them a heap of bad luck, with Sato experiencing multiple mechanical issues, as well as having a wheel falling off after a pit stop in Zandvoort, a race in which he had fought for points.

[13] For the 2023 season, Sato transitioned into sportscar racing, driving for United Autosports in the LMP2 category of the European Le Mans Series alongside Philip Hanson and Oliver Jarvis.

[15][16][17] Following his performances in the European Le Mans Series, Sato was announced to be remaining with United Autosports to make his international sportscar racing debut in the 2024 FIA World Endurance Championship, driving in the newly established LMGT3 class in a McLaren 720S GT3 Evo.

[18] Sato was also originally announced to be competing in the IMSA SportsCar Championship in the LMP2 class for 2024, racing alongside former Formula One driver Paul di Resta, but he later withdrew from the IMSA programme after an upgrade in his FIA driver categorisation from silver to gold, leaving him to "focus fully on the WEC challenge ahead.

"[18][19] In December 2023, United would announce that Sato had signed on for a sophomore season in the ELMS, partnering Ben Hanley and Filip Ugran.