Wigan have announced Uwe Rosler as their new manager after agreeing compensation with Brentford.
Marseille have parted company with manager Elie Baup in the wake of Friday's defeat to Nantes at the Stade Velodrome.
The 18-year-old arrives at Craven Cottage on a free transfer and will be part of the Fulham development squad that will compete in the Barclays Under-21 Premier League.
Plumain represented France at Under-16 level and he made 22 appearances for Lens in the French second division last season, scoring one goal.
He has signed a contract with Martin Jol's team until June 30 2016, with the option of extending the deal for another year.