Shockwave is unique amongst Transformers characters, because, unlike most of his shape-changing robotic bretheren, he didn’t start life as a toy licensed from Takara. He was initially Astro Magnum, a toy that could be found at RadioShack, of all places. Amusingly, some members of the Transformers fandom refer to the pre-TFs toy as “Shackwave,” in honor of his origins.
Anyways, at the time I did the Robot Heroes repaints, this was the only variant of Shockwave of which I was aware. So he gets to be adorable and silvery at you.
Shockwave, Transformers, and all related characters are owned by Hasbro and Takara. I dunno who owns Astro Magnum, but here’s a cool article that goes way too into depth about him.