First of there should not be any confusion between the two words “maybe” and “may be”.
True, maybe he is honest. or It may be that he is honest.OR It is true he may be honest.
In case of “maybe” we use simple sentences and these may contain modals like is am are was were would might etc For example in case of the given sentences– Maybe, the person we we are talking about is not the person we are talking about.
PLEASE NOTE that it is —- “Maybe” and not “May be” and
After this the sentence is to start with small letter.
Otherwise the given other sentences are correct.
In case of still any doubt ,for this as well as any other, your always most welcome