Ask the LLM to describe that author's style. Then start a new chat and tell it what you want it to write, giving it the author's style as a guide but without mentioning the author. While I've never used it for this particular purpose, I've used variations of this technique to get around other blocks quite well.
Yeah similar to how image generators don't draw Mickey Mouse, but ask for a black cartoon mouse with big ears and see what you get!
Seems reliable and effective