1. Does Nintendo have a valid copyright on its characters, music, sounds, and iconography? I think the answer to that question is a resounding yes. As such, the Copyright Act gives Nintendo the authority to control all copies made, including all derivative works.
2. Does an LP video constitute an original work by the author? The answer here has to be no because an LP video is reliant upon the underlying copyright protected work. Because an LP video depends upon a work protected by copyright, it would be considered a derivative work under the Act and would require the permission of the copyright holder, in this instance, Nintendo.
3. Does an LP video fall under fair use and therefore not a violation of Nintendo’s copyrights? This is where the debate hinges. I think a strong argument can be made that LP videos fall under the fair use provision, provided they were created for educational purposes or as a means of instructing other people. If that were the case, the creator of an LP video wouldn’t need Nintendo’s permission and could freely create and distribute their videos without fear of retaliation. .
Whether that derivative work could then be monetized by the creator is a different beast entirely and would require some research on my part, as its admittedly been awhile since I’ve studied copyright law.