The Belgian duo, who recently joined the club, were not on the bench in Saturday's seasonal opener at Cardiff City as they continue to work on their match fitness and assimilation into Schopp's playing style.
Schopp will make some changes for Tuesday night's Carabao Cup tie at Bolton Wanderers, with the likes of Herbie Kane, Devante Cole and Jack Walton, pushing for involvement alongside forwards Oulare and Iseka.
But the Austrian kept coy as to which players will be specifically involved.
On Oulare and Iseka, Schopp said: "First of all, we have to get them both fit and this is the most important thing.
"The second most important thing is to get them used to the way we want to play.
"Both players have a lot of quality. But to see the quality on the pitch, we have to work on the fundamental things. It is all about finding the right moment to bring them (in). I guess we will have a lot of fun with these guys."
On whether he will make changes for the trip across the Pennines, the Austrian continued: "It is likely that some of the guys get the chance to play for a few minutes, probably a bit more.
"It is all about the question of how fit are the guys and we all know how tough the Championship is. We really have to take care about each player, so some players will get a couple of minutes and it is a good thing to get the group bigger.
"The most important thing for me is to see the progress that all the players are getting. Secondly, I want to see more variation in our amount of players and it means every player has a different style and every different style gives us something different."