neutral-coloured vs neutral-colored

neutral-coloured and neutral-colored both are adjectives.

Word	Noun	Adjective	Verb	Adverb
neutral-coloured	No	Yes	No	No
neutral-colored	No	Yes	No	No

As adjectives, neutral-coloured and neutral-colored are synonyms defined as:

neutral-coloured and neutral-colored: having a color that does not attract attention

neutral-coloured (adjective)	neutral-colored (adjective)
having a color that does not attract attention	having a color that does not attract attention