I am curious for the MWC rules and how they would work for RC. Aside form the rules already in play, do these rules have historical specs and performance data as thier reasoning?

Also, as for armament and defenses, both of these warships have the same defenses (about 4in of armor at the belt). Another thing to consider is steel quality. During the time that Japan was industrializing and even well after WW1, Japan had no natural resources, no steel. They imported all their steel and didnt have enough all the time. So, to make more steel, they cut their steel with other less than perfect addetives, like copper (when tungsten, nickle, molybdenum, etc. is required with as mush sulfur elimitation as possible). So, Japanese armor plating is most likely not as good as German steel (the Germans were perfectionists as far as materials and everything productio-wise). That same 4in german plate might have had better mechanical performance (better protection) than the Japanese 4in plate. Additionally, I do not know if Japan specially treated their steels like the Americans did (annealing for tempering and making one side of the plate harder and the other side of the plate softer for superior mechnical performance).

The maneuvering performances are a bit differnt though. The Mogami if I remember, easily busted 30knots (I cannot remember the design spec speed or its sea trial speed). The Graf Spee was maybe 27 knots? So, turning radius aside, the speed of the Mogami will allow it to dictate its firing position.

As for armament, the Graf Spee has a serios advantage. Being on the verge of being a very light battlecruiser, it mounted 11in guns where the Mogami had 8in guns when refitted (though it mounted more barrels, even in the 2x turrets.

If I remember correctly, the German 11in guns had a much better performance than the Japanese 8in guns. The ballistics of the 11in allowed them to shoot much further, and if they score a hit, they went through the 10cm armor much more easily than what the 8in proectiles would. So, the damage of the Graf Spee would have been absolutely devastating to the Mogami (or other heavy cruiser as a matter of fact). Due to the longer range of the 11in guns, the Graf Spee can engage other cruisers well before that can engage it back. The other cuisers, a Mogami for example, would be more nimble as far as speed goes, but they have to charge in some ways under fire before they too can engage the Graff Spee back.

I am curoius if MWC ruls takes all this into account.