The 25-year-old spent the 2018-19 campaign on loan at the Toffees and went on to make 32 appearances for the blue half of Merseyside, making a real impact on the team.
The move, reported by the Express, would be another loan spell for the centre-back with wages being paid by the Toffees, which the club can expect to cost £40,000 per week for the Frenchman.
Will Zouma be hard to prize away?
He has been a regular part of Chelsea boss Frank Lampard's team selection, starting 19 Premier League games.
Zouma still has three years left on his current Blues deal which is why Carlo Ancelotti is keen on agreeing a loan deal with his former club.
The defender is likely to play a key role when the Premier League returns with Chelsea still in the FA Cup and involved in a tight battle for the top four.