[4][5] The 2018–19 campaign saw Sosa become a senior member of the club's first-team, he made his professional career debut in a 2018 Copa Libertadores fixture with Racing Club on 29 August 2018; he featured for the remaining sixteen minutes as River Plate won 3–0.
[1] In February 2021, Sosa signed with Major League Soccer club Atlanta United.
[8] On 6 April 2021, Sosa made his club debut in their 1–0 victory over Alajuelense in the CONCACAF Champions League.
[9] He then scored his first goal for Atlanta United on 4 May 2021 against the Philadelphia Union in the Champions League, the match ending in a 1–1 draw.
[11] Whilst with River Plate, represented the Argentina U20 team; including in training sessions with the seniors.