Should I wear a knee brace when returning to soccer after ACL injury?

Depends. Many sports physicians do recommend a custom acl brace when returning to soccer after acl injury. It often depends on the severity of the injury and whether or not there was any other associated injury. Many athletes find them cumbersome and when they get their confidence no longer use them.
Yes. Although there is no proof in the literature that braces prevent re-injury, we believe that the brace at least gives you a mental reminder about your knee, and may help you concentrate on proper jumping/landing techniques.