wet blanket vs unwelcome person

wet blanket and unwelcome person both are nouns.

Word	Noun	Adjective	Verb	Adverb
wet blanket	Yes	No	No	No
unwelcome person	Yes	No	No	No

As nouns, unwelcome person is a hypernym of wet blanket; that is, unwelcome person is a word with a broader meaning than wet blanket:

Other hypernyms of wet blanket include persona non grata.

wet blanket (noun)	unwelcome person (noun)
someone who spoils the pleasure of others	a person who for some reason is not wanted or welcome