User blog comment:Aphrodite Sweetheart/Official Winx Club WOW and 4th movie discussion blog/@comment-2056915-20160605055319

[UPDATE] Samara Naeymi confirms that she will voice new characters in WOW: The harsh judge Margot and her dog Puff.

So at the moment we know 3 new characters: The villain Jim (of season 2), the judge Margot and her dog Puff.

Source: http://vk.com/winxclubrus?z=photo-41080141_413833914%2Falbum-41080141_00%2Frev

In the case you wanna know who she is: http://www.ncld.org/archives/mission-and-history/our-team/samara-naeymi