I do not let anyone in the page. Have always seen it as a bad idea to give away passwords. But I have a page where there is another author as well. We create the context together in google doc

Login to your website as admin or a user that has admin rights. Create a new user and give them writes to create content (not admin rights).

PitoFly

Click on users in your dashboard and add user there is a location at the bottom to set the user type such as contributor, author and it will generate a secured password when you click add.

Randy

The easy way is to just add another user so they can post under a different name
The problem of course is you will have to share your password for either Wealthy Affiliate or your website with them unless they send you the actual post then you transfer it to the website