The versatile 21-year-old midfielder will join manager Xabi Alonso and his new teammates later in pre-season.
Barco began his career at Boca Juniors, making his professional debut at just 16 after progressing through the club’s academy.
He moved to England in 2024 to join Brighton, before enjoying loan spells with Sevilla and Strasbourg.
Following an impressive 2024/25 campaign, Barco joined Strasbourg permanently and helped the club secure European football. He contributed to 12 goals in 43 appearances across all competitions last season.
His strong club form earned him a place in Argentina’s 2026 FIFA World Cup squad. Barco currently has five international appearances.