The Chelsea duo are free to play against Germany but have not been able to train with the rest of the England squad.
The Three Lions boss has no fresh concerns to contend with heading into the eagerly-anticipated match at Wembley but a decision needs to be taken on the Chelsea duo.
Mount and Chilwell are completing the final hours of isolation having come into contact with club team-mate Billy Gilmour, who tested positive for coronavirus, after the Group D game against Scotland.
The pair missed the Czech Republic win and have had to train separately, before travelling down from St George’s Park away from the main group ahead of their release from restrictions at midnight.
“Clearly, it is really complicated because there’s the physical periodisation you would want for a game like this and then there’s the tactical training,” Southgate said.
“The meetings we’ve had, they’ve had to be in a separate room and dial in on Zoom so the whole experience for them including travelling down tonight is very, very difficult.
“But they are young players who I think can get on with things pretty well.
"私の言ったように, it is a decision I’ve got to take when we’re looking at how they’ve been able to train and everything else. There’s a lot wrapped up in that call.”
Mount started England’s first two matches and is reportedly in serious consideration to start against Germany.
There is also talk that the Three Lions may revert back to a three-man defence flanked by wing-backs at Wembley.
"上手, you always deliberate over those sorts of decisions,” Southgate said of his selection conundrums.
“I think you have clear ideas in your head, but then you train for a reason and you observe people in training and you see whether they’re in form, whether they’re looking sharp, any physical issues they may have.
“You always give yourself time as a team of coaches to make the correct decisions and assess training, review it back.
“I think that’s a process we always go through and then you come to the decisions which hopefully are the right ones.”