Though he isn't quite so well-known in the West, one of the greatest
Transformers illustrators of all-time is
Hidetsugu Yoshioka. In the mid 90s, Takara commissioned him to illustrate a series of "story pages" for the magazine Comic Bom Bom to promote their
Super Turtles and
Metal Turtles toylines. You can find a complete gallery of the pages at
TFPulp, though they aren't of the best quality (they're large, but badly pock-marked).
However, Adam Winters got ahold of one of the issues that featured Yoshioka's art and sent me a high res scan, which you can enjoy below: