in question vs dubitable

in question and dubitable both are adjectives.

Word	Noun	Adjective	Verb	Adverb
in question	No	Yes	No	No
dubitable	No	Yes	No	No

As adjectives, in question and dubitable are synonyms defined as:

Other synonyms of in question include doubtful, dubious.

in question (adjective)	dubitable (adjective)
open to doubt or suspicion	open to doubt or suspicion