Bournemouth manager Eddie Howe has vowed to give his promotion heroes the chance to shine in the Premier League.
Wolves boss Kenny Jackett fears he will lose key winger Bakary Sako after his side missed out on a place in the play-offs.
The 22-year-old, a former France Under-21 international, was given the all clear to switch to the French club following an approach before the transfer deadline.
Gueye, who moved to Goodison Park from Strasbourg in June 2010, has made just six appearances for the Toffees this season.
Brest are currently only four points above the Ligue 1 relegation zone.