The inaugural tournament takes place in Parma, Italy, and provides players an opportunity to gain international experience.
Teams are made up of predominately Under-20 players, but with each union able to select up to three Under-23 players per matchday squad.
Wales kick off their campaign at the Stadio Sergio Lanfranchi on Thursday (09:00 BST).
Net Metcalfe, who has won three senior caps, starts at full-back, while centre Jenna De Vera and back row Jess Rogers are named as co-captains.
Props Maisie Davies and Cadi-Lois Davies, lock Alaw Pyrs and half-back pairing Hanna Marshall and Seren Singleton are also included, having trained with Wales’ senior 2024 Six Nations squad.
“We know France will prove to be an exciting challenge for us and we are all looking forward to it,” said Wales head coach Liza Burgess.
“The teams are all at very different stages in their development and this competition is a great way to measure where we are.
“This tournament is all about us and what we do, and we will know where we stand after this opening game.”
After facing France, Wales play England on 9 July (20:00 BST), then hosts Italy on 14 July (17:30 BST).
Wales: Nel Metcalfe; Eleanor Hing, Kelsie Webster, Jenna De Vera (co-capt), Amy Williams; Freya Bell, Seren Singleton; Cana Williams, Abi Meyrick, Cadi-Lois Davies, Erin Jones, Alaw Pyrs, Lily Terry, Lucy Issac, Jess Rogers (co-capt).
Replacements: Molly Wakely, Maisie Davies, Lowri Williams, Robyn Davies, Catrin Stewart, Katie Bevans, Hanna Marshall, Savannah Picton-Powell.
