Before the second half of 2021–22, Fonseca signed for Uruguayan side
River Plate (Montevideo). In the first week of 2024, he signed for
River Plate of Argentina. In January 2025, Fonseca moved to Mexico, joining
Liga MX side
Club León. On 26 December 2025, he was sent on loan to Spanish club
Real Oviedo, who sat bottom of the
La Liga table, until the end of the
season. ==International career==