While in early production, a fan asked the lead writer for what the dynamic will be like between Sonic and Shadow. And he stated: "The main idea is that Sonic will try to befriend Shadow in a similar vain as Knuckles in Sonic 2. But it's not going to work that way. Because at this point, Sonic has never interacted with someone as emotionally damaged as Shadow."
Shadow is portrayed in the games and other media as a neutral or anti-hero character. So this is accurate.
