Matt Doherty and Leander Dendoncker could feature in the new-look competition as two of the six Wolves players joining senior set-ups this week.
Rui Patricio and Ruben Neves join up with Portugal, while Raul Jimenez will link up with Mexico and Romain Saiss with Morocco.
Diogo Jota is with Portugal under-21s and Ruben Vinagre is an age lower with the under-20s, while Morgan Gibbs-White will hope to feature for England under-19s.
Doherty’s Republic of Ireland face Wales in the Nations League on Thursday before taking on Poland in a friendly on Tuesday.
Summer signing Dendoncker is also competing in the Nationals League, meeting Iceland on Tuesday, after a friendly with Scotland on Friday.
Earning a Portugal recall is Neves and he will hope to impress in friendlies against Croatia (Thursday) and Italy (Monday) alongside Patricio.
Jimenez will head to America to take on Uruguay in Houston and the USA in Tennessee either side of the weekend.
On Saturday Saiss will face Malawi in a Continental Qualifying Match with Morocco.
Jota and Portugal’s under-20s face UEFA Under-21 Championship matches against Romania (Friday) and Wales (Tuesday).
Meanwhile, Vinagre and the under-20s are in friendly action against the Netherlands on Friday and Czech Republic the following Tuesday.
Finally, Gibbs-White is also in friendly action with England’s under-19s, facing Netherlands (Wednesday) and Belgium.
