Factual error: If we had to go by the pre-kickoff aerial shot, Shuutetsu is playing with a 2-3-5, which is definitely not a normal soccer formation - and we never see during the actual play anything close to the team having 5 forwards. Also, the linesmen are infield instead of behind the sidelines. (00:17:05)
The Football Is My Best Friend - S1-E4
Audio problem: When Tsubasa says bye to his friends from the top of the overpass, his mouth is not animated for the greater part of the line. (00:04:30)
Kick-Off for the Future - S1-E3
Trivia: International versions change Roberto's message to his coach at San Paulo FC, adding for some reason that he met a girl he fell in love with. This girl is never referenced nor appears, since, well, she does not exist? Roberto mentions that he met Tsubasa instead, who he wants to bring to greatness. (00:12:40)