This is an interesting question! I am not sure what an "isu" essay is, but assuming it is like any other academic essay, I am not aware of any reason why you should not use some literary devices to write it. I do have a few tips, though, on doing this.
I would avoid hyperbole for the most part. Bear in mind it is essentially exaggeration, and exaggeration is seldom persuasive in an academic essay. You are expected to provide solid evidence to make your main point.
Similes and metaphors can be quite useful and persuasive in an academic essay, particularly metaphors. An extended metaphor can be very effective. However, you want to be very careful and not pile on similes and metaphors because, while you want to be creative in your writing, your assignment is not a creative writing paper.
Remember to use literary devices only to strengthen your main idea and to give your reader a "picture" that will persuade the reader of what you have to say.
It might be a good idea to submit another question and explain what an "isu" essay is. Then we can give you examples of how you might use literary devices in your assignment.
Well, it is basically an essay where you choose to read a book and then write about a topic (character development, theme etc). In my case I've read To Kill a Mockingbird and I'm writing about Scout's maturity throughout the book.