23-year-old Roberts, a product of the regions academy comes in to win his second international cap in a complete revamp of the Welsh midfield.
Watkin meanwhile returns to the side having started the campaign against Scotland. Both Ospreys George North and Saracens Nick Tomkins the players replaced are not not included in the 23.
Gatland has also opted to move captain Dafydd Jenkins from the second row to blindside flanker, with Will Rowlands coming in to start alongside Adam Beard in the front row.
There is also a change at hooker with Scarlets Ryan Elias getting the nod over Elliot Dee who will have to wait to win his 50th cap for his country.
Cardiff’s Alex Mann, who has started the first three matches at number six, is named on the bench that also sees the return of experienced scrum-half Gareth Davies.
Wales head coach Warren Gatland speaking on the changes said:
“There are a few changes to the team this week as there are some players that deserve an opportunity.
“It’ll be a tough, physical challenge from France on Sunday particularly up front. We know they will start hard and it’s about us staying in the fight, having good line speed defensively and keeping our discipline. We’re looking for an 80 minute performance.
“We’re excited to be back at home for our last two matches and looking forward to getting out in front of a passionate Welsh crowd this weekend.”
Wales XV to face France:
Cam Winnett, Rio Dyer, Joe Roberts, Owen Watkin, Josh Adams, Sam Costelow, Tomos Williams, Aaron Wainwright
Gareth Thomas, Ryan Elias, Keiron Assiratti, Will Rowlands, Adam Beard, Dafydd Jenkins (captain) , Tommy Reffell.
Replacements:
Elliot Dee, Corey Domachowski, Dillon Lewis, Alex Mann, Mazenzie Martin, Gareth Davies, Ioan Lloyd, Mason Grady.
[Lead image: Welsh Rugby Union]
