The 19-year-old has attracted interest from across Europe following a standout season in Japan's J1 League, where he scored six goals in 19 appearances after winning the best young player award, and an outstanding showing at the AFC Under-23 Asian Cup in January — where he was named MVP and finished joint top scorer with four goals as Japan retained the title.
Valencia's owner Peter Lim sanctioned the operation from Singapore after CEO Ron Gourlay received approval to proceed. The club has confirmed a fee in the region of €4 million, a sum covering both the transfer and the player's wages.
The hold-up lies in the distribution of Sato's commercial rights. Valencia want a significant share of what could prove to be a lucrative portfolio. Japanese footballers who break through at European clubs tend to attract major sponsors across Asia, and Sato — not yet 20 and already an established figure in Japan — represents precisely that kind of commercial opportunity.
The Mestalla hierarchy see the deal as viable on multiple levels. Sato offers attacking versatility, an eye for goal and speed to exploit space, while his profile carries serious marketing potential throughout Asia. That dual appeal is central to the club's calculation.
His preferred position is left wing, despite his stronger right foot, which allows him to cut inside and create. He can also operate across the attack, giving coach Carlos Corberán options in transition.
Sato came through the FC Tokyo academy and made his professional debut at 16. A loan spell at Fagiano Okayama in 2025 produced five goals and two assists in 28 matches. He returned to Tokyo this season and was named the J1 League's best young player before Valencia moved to secure him ahead of Dutch club Feyenoord, who had also submitted an offer.
The image rights question is the remaining hurdle. Once that is resolved, Sato is expected to join Corberán's squad for the new season.