crucial vs of the essence

crucial and of the essence both are adjectives.

Word	Noun	Adjective	Verb	Adverb
crucial	No	Yes	No	No
of the essence	No	Yes	No	No

As adjectives, crucial and of the essence are synonyms defined as:

Other synonyms of crucial include all-important, all important, essential.

crucial (adjective)	of the essence (adjective)
of extreme importance; vital to the resolution of a crisis	of the greatest importance
of the greatest importance
having crucial relevance