From Chelsea's Kovacic article
The signing of Kovacic puts Chelsea under pressure to sell or loan out at least one foreign player to fulfill Champions League squad guidelines. Everton want to sign central defender Kurt Zouma permanently.
Hopefully this helps, cant see what other 'foreign' player they could get rid of for decent money who may not be 1st choice.
Willian is gagging for a move.
Seems strange tho, they lost Hazard, bought Pulisic, Kovacic was already there, am I missing something?