I'm a great Özil fan but technically they're very, very similar. Which makes sense simce Havertz himself named him as a role model. Özil still is a better passer but IMO he's the best final third passer of his generation, even better than Messi in this aspect, so that doesn't say much. Havertz still plays some incredible passes at times. On top of that, he significantly faster (has one of the highest top speeds of the BL, exceeding 35 km/h), a waaayy better finisher, is stronger and has a real goal instinct. Overall a much more complete footballer than Özil who sadly stopped developing after leaving Madrid.