The Confederacy believes in Starfleets Mandate, they just don’t believe in the Federation anymore. As such a Science Vessel was needed. The Wonder class was designed by the Federation at a time when they though that a larger science vessel would be needed. It was ultimately canceled with Scientific and Light Explorers like the Norway and Intrepid were put into production. The Wonder class was revived by the Confederacy to fit their need. The design was one of the canceled designs stolen by defecting members of the ASDB when they went to the Confederacy.