This does not directly address my question that you have quoted. It appears to me that your previous responses to my earlier posts in this thread have done similar things. I am not asking about things that potentially may happen based on your own personal opinion of US copyright law. I asked,
I have been unable to find any instances of such.
Artists having sold the rights to their work but then using it again in other work for profit - thus committing copyright infringement - is obviously not controversial: you 100% can commit copyright infringement against work you created, once you have sold the rights to it. I am sure one of the lawyers here can weigh in, but if, for example, I record a song, sell you the rights to that song, then record another song where I substantially sample the first without your permission and without significantly altering it, then I absolutely will have committed copyright infringement against you, the copyright holder, regardless of the fact that I created both works. That's just not in question, is it? That's the whole point of buying a copyright: to gain control over the commercial use of someone else's creation.
So I assume what you are looking for is cases more like the Fogerty one, where artists are charged with plagiarizing their own
style and thus committing copyright infringement. I don't know if there are any other cases exactly like that one in the US; the judgement seems pretty clear. And to be fair, that case seems to have been motivated more by personal animus rather than the plaintiff actually having much of a chance to push copyright that far.
Note that plagiarism is not normally illegal in the US or Canada, copyright infringement is. Plagiarism is the term normally used in academia, and you absolutely can plagiarize yourself. We warn students against it at the start of every course, and pretty much every university has specific rules about it. However, self-plagiarism can also be copyright infringement, which is why students and academics are warned that it "can involve copyright infringement if you reuse published work" (for example, by publishing an essay in one journal and then again in another, if you signed an exclusive deal with the first. There are many cases of this happening).
Again, none of this is controversial. The Fogerty case was controversial because he
didn't reuse the work to which he had sold the copyright, but published new work that sounded (somewhat) similar, and the copyright holder consequently tried to argue that, in effect, he owned Fogerty's musical style. Mostly because he hated Fogerty.