The 22-year-old Oviedo, who can play at left-back or on the left side of midfield, has been a regular starter for the Danish side after joining them from Deportivo Saprissa in his homeland.
With Everton boss David Moyes in London to finalise the deal, assistant coach Steve Round said that the club had been monitoring him for some time and that a deal looked likely.
"But as yet he is not our player. We have work permits to get. That is why the manager is not doing the press today - he is in London trying to tie that up and finalise it.
"Until it's all done we can't really comment too much, but I think later in the day it will all become clearer and when he puts pen to paper we can talk about the player.
Source: AFP
Source: AFP