Joe appears as Lan Hikari's teacher in the Central Town School. He's kind, but strict. During BlastMan's attack on the school he gets stopped by rogue security robots while trying to protect the students and is overpowered. He gives Lan his teacher card so that he can get into the faculty room and access the controls there.
Joe appears again when Dr. Wily asks the operator of BlastMan.EXE to appear. He helps Blackbeard and DiveMan.EXE to kidnap MegaMan.EXE. They succeed and when Yuika, Ito, and Vic decide to turn against the WWW, he refuses and leaves the group. When Lan went after the ex-WWW members who kidnapped Iris.EXE, Joe arrives to save them and Baryl. He also reveals his reason for joining the WWW. His daughter was sick with a deadly disease and he couldn't pay for an operation to cure her. But, Dr. Wily appeared and paid for the operation. Indebted to Wily, Joe joins WWW and started working undercover in the school, spying on the WWW benefactor, Mayor Cain. He also explains his relationship to Baryl. In a martial arts competition, he was defeated by Baryl and asked to train under him. Baryl accepted and they've been friends since.
When Lan and Chaud are cornered by Heel Navis, Joe saves them by distracting the Navis and leading them on a wild goose chase. In the ending, Joe was given a lighter punishment compared to the other WWW members, and appears one last time when all the students are graduating. He tells his students good luck and congratulates them.
- Joe and BlastMan are the only WWW members to not appear in the MegaMan NT Warrior anime series.
- Joe Mach’s name might be a reference to the Mach number, a number named after Austrian Physicist Ernst Mach comparing the speed of an object to the speed of sound, which is often used as a unit of velocity in aeronautics and other high-velocity fields of science.