country of origin vs motherland

country of origin and motherland both are nouns.

Word	Noun	Adjective	Verb	Adverb
country of origin	Yes	No	No	No
motherland	Yes	No	No	No

As nouns, country of origin and motherland are synonyms defined as:

Other synonyms of country of origin include fatherland, homeland, mother country, native land.

country of origin (noun)	motherland (noun)
the country where you were born	the country where you were born