of unsound mind vs non compos mentis

of unsound mind and non compos mentis both are adjectives.

Word	Noun	Adjective	Verb	Adverb
of unsound mind	No	Yes	No	No
non compos mentis	No	Yes	No	No

As adjectives, of unsound mind and non compos mentis are synonyms defined as:

of unsound mind and non compos mentis: not of sound mind, memory, or understanding; in law, not competent to go to trial

of unsound mind (adjective)	non compos mentis (adjective)
not of sound mind, memory, or understanding; in law, not competent to go to trial	not of sound mind, memory, or understanding; in law, not competent to go to trial