The 25-year-old spent the second half of the 2024-25 season on loan with AC Milan after failing to secure regular first-team football at Chelsea.
Milan have opted against signing the playmaker following the dismissal of Sergio Conceicao and just three goals in his 21 games.
Felix now looks set to leave the Premier League side once again this summer and is in talks with boyhood club Benfica, according to CaughtOffside.
Benfica are pushing for a loan move while Chelsea want to get rid of him on a permanent basis just one year after he joined.