This is the first time Wonder Woman is mentioned in the DCAU. At first this may seem to also represent a continuity error, since Wonder Woman will not appear in the outside world for another four years. However, Wonder Woman was one of Justice League members who traveled back in time to World War II in the Justice League (2001) episode The Savage Time: Part II (2002) to stop Vandal Savage. In The Savage Time: Part III (2002), we see the elderly Steve Trevor remember Wonder Woman from his fighting days in World War II. It's possible Trevor and others remember Wonder Woman and told tales about her from the time she assisted fighting with the allies in World War II.
Though there doesn't appear to be a direct canonical tie-in, the designs of the Kryptonian military armor and sonic-emitting helmet used by Jor-El in the episode had a very clear influence on the character design of Shriek, a sound-based villain from the TV series, Batman Beyond of which was later created by Bruce Timm and Paul Dini.
Included as one of Bruce Timm's Picks on the bluray release of All-Star Superman (2011).