Jean-Philippe Gbamin plus defenders Mason Holgate and Vitalii Mykolenko have not travelled with Everton's squad to Switzerland.
Everton defender Seamus Coleman has signed a new one-year contract.
Everton midfielder Tom Davies will leave the club when his contract expires at the end of the month after turning down a new deal, the club have announced.
Former Everton goalkeeper Asmir Begovic believes the club's inconsistent ownership has complicated matters for players and staff.
Conor Coady has left Everton and returned to Wolves following his loan spell with the Toffees.
Abdoulaye Doucoure scored the most important goal of his career and possibly Everton’s history to save the side from relegation with a 1-0 win over Bournemouth.