Board Thread:Support Requests - Designing Your Wiki/@comment-37218846-20200208124852/@comment-9605025-20200209233014

I am not sure what you mean by "require any policies". Anyone can rename their account provided they have not previously renamed the same account. The username restrictions are the same between renaming an account and creating an account. This includes the requirement that neither the name nor a "similar" name has been or is currently in use.