For example: One nation builds their heavy cruisers with heavy armour but lighter guns while another nation builds theirs woth larger guns but lighter armoured.
Or were there no large differences?
There's some discussion about differences between warship design in WWII here, written by both myself and /u/DBHT14. Essentially, there were great differences in how navies designed their ships in both world wars, depending on how each navy planned to fight battles, the money available, the threats that they expected to face, treaty limitations, and the preferences and abilities of naval designers and constructors.