Or 'An answer to the question: What if the Fuso had become the template for all Japanese battleships after 1915?'

AU Profile: The Izumi-class were designed essentially as a last hurrah to the classic Japanese battleship. Their odd arrangement is a vestigial tail from the Fuso and Ise classes, although their turrets and elements of their superstructures more closely resemble the later Yamato-class. Later members of the class would see conversion to hybrid battleship-carriers and pure aircraft carriers during the 60s.

Those aren't 18-inch guns by the way. I've looked at the barrel length and turret size, and they roughly correspond to how large I'd reckon a long calibre 560mm or 22-inch gun would be. So yeah, 18 560mm gun broadside. Happy days :D