Nadjim Abdou has accepted Plymouth's offer of a one-year deal.
The 23-year-old, who left Sedan earlier this summer, has been on trial at Home Park and impressed manager Ian Holloway.
Abdou has been considering his options, but he has decided to accept the offer from the Devon club.
"He looks like he's got something that we haven't, and I can work with him trying to [play on] that right-hand side," said Argyle boss Ian Holloway.
"I think he can, with the skills that he's got. He hasn't before, but I think I can easily teach him how.
"It might take a few weeks but it looks like he's got the right qualities to do that."
Meanwhile, Holloway has also reiterated his desire to re-sign Chelsea's Scott Sinclair.
The youngster had a successful spell at Home Park last season and Holloway is trying to bring him back.
"Is Scott Sinclair going to play for Chelsea, with Florent Malouda and all of them? I can't see it myself, so I am gonna be desperately trying for that again," he added.