He fights nothing like Marquez. They both like to counter, that's about the end of the comparison.
Marquez often worked behind a jab, and was more of a classic, patient counter puncher in that he waits for the opponent to do something, and perfectly times counters between shots. He also unloads with combinations frequently, has an amazing left hook, goes to the body often, and doesn't mind punching with opponents.
Conor is a one trick pony who pesters opponents into overcommiting, with the right hand probing them etc, then nails them with the straight left. That's basically it. And more aggressively provokes his opponent into countering than Marquez.
If there is one figher in boxing history that has some similarities, it's actually Hamed. He was also a one trick pony with a counter straight left, and a lazy right jab that served no purpose but to pester opponents and setup the left.
Golovkin is a better example of an aggressive counter puncher. He's constantly forcing his opponents to do something, trapping them on the ropes, in corners, and forcing openings to unleash big shots, and guiding opponents into his big shots.