Fabian Delph and Bernard are both unlikely to return to action in Saturday's home game against Norwich.
Delph has been sidelined due to a hamstring strain and forward Bernard has been out since sustaining a knee injury in last month's defeat at Brighton.
Bottom club Norwich could be boosted by the return of defender Christoph Zimmermann from the foot injury which has ruled him out since the end of August.
Full-back Jamal Lewis is sidelined by the knee problem which forced an early return from international duty with Northern Ireland, but midfielder Kenny McLean should be available along with Finland striker Teemu Pukki.
Swiss forward Josip Drmic faces up to six weeks out with a hamstring tear picked up against Watford, while centre-backs Grant Hanley (groin) and centre-back Timm Klose (knee) continue their own rehabilitation.
Everton provisional squad: Pickford, Mina, Holgate, Digne, Sidibe, Richarlison, Davies, Schneiderlin, Walcott, Sigurdsson, Tosun, Lossl, Keane, Baines, Coleman, Kean, Iwobi, Calvert-Lewin.
Norwich provisional squad: Krul, Aarons, Godfrey, Tettey, Byram, Trybull, McLean, Buendia, Stiepermann, Hernandez, Pukki, Fahrmann, Zimmermann, Vrancic, Roberts, Cantwell, Amadou, Srbeny