Harper is on pace for 1 bWAR this year. (WAR doesn't like his defense). Going into the season, he and Machado were going to be the darlings of this huge free agency class. Machado is on pace for 3-4 WAR this season. (WAR doesn't like his defense either).
I still think they both get paid a ton and Harper ends up in NY but I'm not sure either of them tops Stanton's contract, although it'll be close.