G.I. Joe Sigma 6 is an animated series produced by 4Kids Entertainment and animated by the japanese animation studio Gonzo aired between 2005 and 2006 which is a re-imagination of the 1980's animated series G.I. Joe, The series had mixed reception between G.I. Joe fans, which led to lit being a failure.
According to Wikipedia, G.I. Joe Sigma 6 was aired on TV Tokyo and Animax, but no recordings of it can be found online, The show appears listed on the page of Studio Gonzo of the Japanese Wikipedia despite that it does not have an article about the show, the show can be found on japanese websites but only on english.
The names of the persons who were involved in the show's animation and designs are known, their names appear in the credits at the end of every episode of G.I. Joe Sigma 6.