[3] On 17 December 2018, Fernández moved abroad and signed for Paraguayan Primera División side Guaraní, on loan for one year.

[7] On 29 March 2022, Fernández agreed to a loan deal with Campeonato Brasileiro Série A side Santos until the end of the year, with a buyout clause.

[9] Fernández scored his first goal for Peixe on 12 May 2022, netting his team's third in a 3–0 Copa do Brasil home win over Coritiba.

On 6 December 2022, Fernández signed a permanent three-year contract with Santos, as the club activated his buyout clause.

[11] On 18 January 2024, Fernández was loaned to Argentine Primera División side Newell's Old Boys until the end of the year.