The former Liverpool prospect is out of contract in the summer and Wanderers may cash in now.
Ngog is also on Premier League wages of over £30,000-a-week at the Reebok and moving him out would give boss Dougie Freedman funds.
Evian made the French Cup final last season and their backers are always in the market for 'name' players.
Ngog has turned down a recent move to Turkey but admitted that he would be interested in a switch to France.