Synonyms for Inessential:

adj.

all (adjective)
unessential.
immaterial (adjective)
meaningless.
unimportant (adjective)
irrelevant, superficial, minor, of no consequence/of little consequence, unconsidered, petty, unimportant, inconsequential, mere, meaningless.
unnecessary (adjective)
dispensable, nonessential, uncalled-for, needless, unessential, irrelevant, unrequired, unneeded.
unsubstantial (adjective)
vacant, intangible, impalpable, illusory, chimerical, unconcrete, nonexistence, insignificance, unreal, weightless, immaterial, ethereal, tenuous, null, empty, apparitional, phantasmal, unsubstantial, spectral, vacuous.

n.

inessential (noun)
nonessential, complementary, unessential, complemental, completing, incidental.
object (noun)
nonessential.

Other synonyms:

unrequired. uncalled-for, dispensable, needless.