Ryan Giggs’ side face Finland in Helsinki on Thursday 3rd September (7:45pm), before returning to Cardiff to take on Bulgaria at Cardiff City Stadium on Sunday 6th September (7:45pm).
Roberts, 21, made 23 appearances for Leeds last season, scoring four goals as the Whites won the Sky Bet Championship title.
The forward has won seven caps for Wales, last featuring for the Dragons against Croatia in October 2019.
The Republic of Ireland are the other team battling alongside Bulgaria, Finland and Wales in the Nations League in Group B4.