blend in vs blend

blend in is not a noun while blend is a noun.

Word	Noun	Adjective	Verb	Adverb
blend in	No	No	Yes	No
blend	Yes	No	Yes	No

As verbs, blend is a hypernym of blend in; that is, blend is a word with a broader meaning than blend in:

Other hypernyms of blend in include coalesce, combine, commingle, conflate, flux, fuse, immix, meld, merge, mix.

As verbs, blend in and blend are synonyms defined as:

Other synonyms of blend in include go.

blend in (noun)	blend (noun)
	the act of blending components together thoroughly
	a new word formed by joining two others and combining their meanings
	an occurrence of thorough mixing

blend in (verb)	blend (verb)
cause (something) to be mixed with (something else)	mix together different elements
blend or harmonize	combine into one
	blend or harmonize