Musashi and Yamato had a sister ship, the Shinano. Shinano was converted to an aircraft carrier while under construction. It was the largest aircraft carrier built during World War II. An American submarine sank her 10 days after she was commissioned. U.S. intelligence did not know she existed. The American submarine commander was not believed when he first reported what he sank. There is a good book on that.
I think Shinano was the only vessel Archerfish sank.