You mean fast Battleship, they never were dreadnoughts to begin with, they were first CC's (Battlecruisers) before the retrofit
Any battleship(or battlecruiser) that follows HMS Dreadnought's original design philosophy, i.e. sloped citadel roof('turtlebacking'), single main gun caliber, can be described as a Dreadnought, WW1 era Battlecruisers were in effect battleships with reduced armor, the Kongou-class is very much a dreadnought. additionally, Kongou was designed by George Thurston, a man who worked under Philip Watts, the designer of HMS Dreadnought, namesake of the type of BB
For those who may not know, during the 1920s~30s, Hiei was converted into a training ship due to Washington Naval Treaty. Hence, her role as a teacher. During her refit as fast battleship, her superstructure was rebuilt as a prototype for Yamato-class. Hence, the tower mast on the blackboard and Yamato & Musashi being the students. The research the artist made is commendable.
For those who may not know, during the 1920s~30s, Hiei was converted into a training ship due to Washington Naval Treaty. Hence, her role as a teacher. During her refit as fast battleship, her superstructure was rebuilt as a prototype for Yamato-class. Hence, the tower mast on the blackboard and Yamato & Musashi being the students. The research the artist made is commendable.
Also, on a technicality because they never had the time to actually do it, Hiei was never officially redesignated as a Fast Battleship. She was still listed as a Practice Gunnery Ship up until the time of her sinking.