Aston Villa and Chelsea have already agreed a loan-with-obligation arrangement to take Garnacho to the Midlands, a deal struck shortly after Villa completed the £117m sale of Morgan Rogers to Chelsea.
Jackson has emerged as one of several names discussed between the clubs since, with Villa boss Unai Emery a long-standing admirer of the Senegal international from their time together at Villarreal, where he handed the forward his senior debut in 2021.
Jackson spent last season on loan at Bayern Munich, largely as understudy to Harry Kane, and made just 15 starts across all competitions. Chelsea, who paid Villarreal around £32m for the striker, are understood to be seeking closer to £65m for his services, given he still has several years left on his contract.
The structure of any further business between the two clubs is critical, with both Chelsea and Villa needing to comply with UEFA's squad cost ratio rules as well as separate settlement agreements reached with European football's governing body in 2025.
Rogers' departure is expected to generate Villa a significant accounting profit, potentially in excess of £80m once Middlesbrough's sell-on clause and the remaining book value of his 2024 signing are factored in.
Had Chelsea sold Garnacho to Villa as part of the same transaction, UEFA would have treated it as a swap deal, cutting into that profit margin. Even with Garnacho's move completing before deadline day, the gap between the two deals falls short of UEFA's 45-day guideline, making it harder for the clubs to argue the transfers are unconnected.
A loan with an obligation to buy could still, in theory, be viewed as part of a swap under UEFA's rules, since the obligation is considered agreed within that window.
However, the conditions attached give Villa control over exactly when the deal is completed, offering the two clubs potential room for manoeuvre with regulators as they continue talks over Jackson.