Abdoulaye Doucoure wanted to join Everton last summer but Watford refused to sanction his move to Goodison.
A reunion with Marco Silva was part of the appeal for Doucoure but the Blues, who have retained their interest, believe the midfielder remains keen on the switch.
Everton saw two bids - the second of which was worth £36m - rejected last summer as Watford refused to sell their key midfield man.
The Hornets are said to want between £30-25m for the 27-year-old this summer following their relegation to the Championship but the Blues are refusing to pay over the odds for the player.
Silva saw Doucoure as a key target in both of his summer transfer windows at Everton but was unable to land the player with Watford digging their heels in.
The interest in the player did not go when Silva was sacked last season and the Blues have put Doucoure on their midfield shortlist alongside Napoli's Allan.
Michael Keane, meanwhile, has been the subject of a story in Spain which claimed that new Barcelona boss Ronald Koeman had identified the Everton centre-half as one of three key targets this summer.
Keane was named alongside Memphis Depay and Donny van de Beek are the players Koeman had told the board at the Nou Camp he wanted to sign, in a report.
The ECHO understands that Keane is not on Koeman's wishlist, however.
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