I struggled to word this question.

Let's say that I wish to work on a project to benefit Tildes (I don't currently have an idea, but just for example). Anything I did, I would like to keep opensource and would encourage other users to contribute. But I would like to keep everything linked to my pseudonym as not to dox myself.

However, I would like to have a copy of everything on my personal GitHub as well, because I am a professional programmer and that is effectively my CV.

Is there a good way to mirror a repo in a way that any git history contributed by me, "John Smith", is changed to "bugsmith" on the mirrored repo? (or vice versa).