what is the one word substitute for”he or she is the wrong actor for that part or role?
Does misfit or unfit suit the purpose?
I would like to know the noun for the sentence
The usual way to say
Kim is the wrong actor for that part or role.
Kim is miscast in that role.
Lexico has miscast as a verb, above is the adjectival use of the verb.
1 Allot an unsuitable role to (an actor)
he is badly miscast in the romantic lead
Lexico does not classify miscast as a noun and it would be very unusual to say
Kim is a miscast.
as if there is a similarity with misfit, which anyway is not used in this context.