The Football Is My Best Friend - S1-E4
Other mistake: In the opening longshot of the Shuutetsu sparring match with Mizukoshi, the side on the right has 10 players instead of 11. (00:07:15)
Other mistake: When Teela is at Snake Mountain, she overhears TrapJaw saying how Skeletor's electrical creature will control all of the machines at the palace. When Teela returns to He-Man, she says that the creature Skeletor created is called Byte. There's no way for Teela to know the name of the creature, since TrapJaw never referred to it by name. (00:14:24 - 00:15:20)