The loan carries a mandatory buy option of €8m that Espanyol will have to exercise at the end of the season provided the winger reaches a modest number of appearances, with Bayern Munich covering part of his wages for the campaign in the meantime.
Zaragoza passed his medical at the Clínica Corachán on Thursday morning before the move was confirmed, becoming the club's sixth signing of the summer. González had been explicit for weeks about wanting a forward capable of unbalancing games from either flank, and Zaragoza's dribbling and directness fit that profile directly.
The Málaga-born 24-year-old has struggled to settle since his breakthrough at Granada, where two goals against Barcelona in 2023 helped trigger Bayern's decision to pay his €15m release clause.
Since then he has been loaned to Osasuna, Celta Vigo and Roma without ever fully establishing himself, and Espanyol are hoping regular football in a system built around his strengths can finally unlock the form that first made him a Spain international.
The negotiation with Bayern was described internally as smooth, with the German club willing to accommodate a structure that suited Espanyol's more modest resources rather than insisting on an outright sale.
Zaragoza had other offers on the table, including interest from elsewhere in LaLiga and from Saudi Arabia, but opted for Espanyol after the club's initial approach for academy winger Arnau Ortiz gave way to the bigger opportunity once Bayern signalled its willingness to do business.
His arrival is expected to be the club's last major piece of business this window barring further departures, closing out a deal that Monchi and González had targeted since the market opened.