Some US universities do this remotely via proctoring software. They require pencil and paper to be used with a laptop that has a camera. Some do mirror scans, room scans, hand scans, etc. The Georgia Tech OMS CS program used to do this for the math proofs course and algorithms (leet code). It was effective and scalable. However, the proctoring seems overly Orwellian, but I can understand the need due to cheating as well as maintaining high standards for accreditation.