Both players have been released by their clubs despite fitness concerns.
Rooney in particular has missed much of Manchester United's pre-season amid speculation over his future, but Three Lions manager Roy Hodgson is keen to prepare his squad for key World Cup qualifiers next month.
"We realise that this fixture may not have come at a convenient time for the clubs and I am fully aware that they have important games coming up at the weekend," Hodgson told The Mirror.
"They know I will be sensible with their players. I can assure the fans we are absolutely dedicated to reaching the finals. We will leave no stone unturned."
England face Scotland at 8pm on Wednesday, with striker Rooney and midfielder Wilshere earmarked for 45 minutes each.