The 22-year-old Aaronson made 36 Premier League appearances for Leeds last season after joining from Red Bull Salzburg for a fee close to £25 million ($32 million) in the summer of 2022.
He scored one goal in 40 appearances in all competitions for Leeds. He is the third player to leave on a season-long loan following relegation.
Diego Llorente and Robin Koch joined Roma and Eintracht Frankfurt, respectively, in similar deals earlier this week.
Former Norwich boss Daniel Farke has been hired as head coach and charged with the responsibility of trying to guide the club back to the Premier League.