How to hide WordPress users’ names externally?

I have several users creating posts in WordPress, but I don’t want any of their names to appear publicly. On the site, I want it to only say By: Website Editor.

This also means that the names should not appear in any other related URLs, for example author URLs. If someone were to visit for example, it should not reveal any names. I don’t mind disabling author URLs completely if that’s easier to do.

The SEO plugin I use also shows the name of the author in the source, that’s gotta go away also.

And in the backend, the names should appear just like usual.

How could I achieve this?