He seemed to do fine there in a pinch last spring for Brighton but I'd be wary about planning for that to be his primary position. He has played 222 professional matches and only 10 of them as a CB, per Transfermarkt. He is also 5'7 which matters less in a three but definitely not the ideal physical profile.
Realistically, most players who have ACL surgery don't get back to their best until 12-18 months after the surgery. They may get on the field much earlier like Chilwell but it takes time to regain confidence in your body as well as fitness and form after such a long layoff. I think that is the primary issue.