Incognito, alias, stage name, or nickname. A name someone uses instead of their real name, especially on a written work.
A pseudonym is a name which someone, usually a writer, uses instead of his or her real name. “Both plays were published under the pseudonym of Philip Dayre”.
A name that someone, often a writer, uses instead of their real name. A name that a person or group assumes for a particular.
A designated authority may be able to revoke the pseudonym. Or synonyms as nickname or pen name.