of the essence vs all important

of the essence and all important both are adjectives.

Word	Noun	Adjective	Verb	Adverb
of the essence	No	Yes	No	No
all important	No	Yes	No	No

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

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

of the essence (adjective)	all important (adjective)
of the greatest importance	of the greatest importance