Everton already completed their second transfer of the January window as they try to address problem areas in their squad.
Nathan Patterson joined the Toffees from Rangers on Tuesday on a contract that runs until 2027. The Scottish right-back cost £10 million, BBC Sport's Brian McLauchlin and Phil McNulty report.
Everton signed left-back Vitaliy Mykolenko from Dynamo Kyiv for a reported fee of £18 million on New Year's Day.
Rafa Benitez's position as Everton manager is under scrutiny after his team fell to 15th in the Premier League table following Sunday's 3-2 home defeat to Brighton & Hove Albion.