This add-on allows you to create threads and posts as if you were another user. All you need to do is enter a username.
This is possible when using quick reply, the full reply form and when creating a thread.
It is fully permission controlled, and there is a node-level permissions controlling...
What does this add-on do?
Members (primarily administrators or moderators) who have been granted the 'Post as different user' permission can select a user's name from a drop down menu when creating a new thread or posting a reply to create a post on behalf of that user.