One way or another, the art is almost never exactly the same. This is the exception, since this exactly alike.
We can all tell Oda inspired from Toryiama, but the art, since the beginning of One Piece, was never like it. It captured the feel of Dragon Ball, yet was pretty diferent. Fairy Tail is just a copy, down to the faces, down to the little animals, down to the style. It's the same shit. The only diference is that Fairy Tail probably derives its gaining popularity from fanservice.