Sevilla's move for Stassin is the most advanced of the three, with the Belgian forward already left out of Saint-Étienne's squad for Monday's Ligue 2 match at Dijon as talks entered their final stages.
According to journalist Sacha Tavolieri, the deal is structured as a loan worth €2.5m with a non-obligatory purchase option of €25m, of which Saint-Étienne would retain 20% of any future sell-on.
Stassin, 21, arrived at Saint-Étienne from Belgian side Westerlo in 2024 for around €10m and scored 12 goals in his first season in Ligue 1 before Saint-Étienne's relegation to Ligue 2, where he added 11 goals and nine assists last term.
The Deivid Washington deal is more convoluted. After missing out on George Ilenikhena, Conrad Harder and Petar Ratkov earlier in the window, Sevilla turned to the 21-year-old Brazilian, but he is not currently owned by Chelsea outright — Strasbourg, who share ownership group BlueCo with the London club, have agreed to sign Washington from Chelsea for around €16m with the specific intention of loaning him straight on to Sevilla.
Washington joined Chelsea from Santos for a similar fee in 2023 but made only a handful of senior appearances, returning to Santos on loan last year before spending the 2025-26 season largely with Chelsea's under-21 side. Sporting director José Ignacio Navarro's staff see him as a natural partner for Robbie Ure and Isaac Romero up front.
For the wing, Sevilla have identified Lille's Félix Correia as a target following the departure of Oso. According to L'Équipe, Sevilla are negotiating a loan with an option to buy for the Portuguese international, who joined Lille from Gil Vicente for €7m last year but has fallen out of Bruno Génésio's plans.
The 25-year-old, who also holds São Tomé and Príncipe nationality, would arrive with market value estimated at around €10m, meaning any purchase option would likely be set below that figure.
Much of Sevilla's business this deadline day hinges on generating funds through departures. The club are working with the lowest squad cost limit in LaLiga, at around €22m, and had been counting on the sale of winger Rubén Vargas to Olympiacos — a deal in the €12-15m range that has stalled in recent hours over economic disagreements between the two clubs.
Should that sale go through before Tuesday's deadline, it would give sporting director Navarro the financial flexibility to complete some or all of the incoming deals still in motion.