shogun vs Japanese

shogun and Japanese both are nouns.

Word	Noun	Adjective	Verb	Adverb
shogun	Yes	No	No	No
Japanese	Yes	Yes	No	No

As nouns, Japanese is a hypernym of shogun; that is, Japanese is a word with a broader meaning than shogun:

shogun: a hereditary military dictator of Japan; the shoguns ruled Japan until the revolution of 1867-68
Japanese: a native or inhabitant of Japan

Other hypernyms of shogun include Nipponese, dictator, potentate.

shogun (noun)	Japanese (noun)
a hereditary military dictator of Japan; the shoguns ruled Japan until the revolution of 1867-68	the language (usually considered to be Altaic) spoken by the Japanese
	a native or inhabitant of Japan

shogun (adjective)	Japanese (adjective)
	of or relating to or characteristic of Japan or its people or their culture or language