It’s a battle of two of DC”s strongest fighters. Both of these guys could go toe to toe against Superman and their abilities are roughly equal. In a standard fight, Black Adam is typically a little stronger and faster. That being said, this is composite so the tides change quite a bit. Shazam once became Lord Marvel and his abilities were greatly enhanced. With this, Shazam destroys the gap between them and he is at a level where he could beat Black Adam. Shazam wins.