Informally, vin09, both of those sentences can pass muster in conversation without getting challenged from a grammar standpoint. Formally, however, you would be much better off expressing them in either a simple "don't" parallel construction or a "neither...nor" construction, as follows:
1. Parallel "don't" construction: "Please don't plagiarize or generate your essay using AI."
2. "Neither...nor" construction: "Please neither plagiarize nor use artificial intelligence to generate your essays."
