Well, since you haven’t encountered Albedo yet at this point in time, that’s a good thing to hope.

Sometime within about a year after the end of the Tennyson Summer Vacation, Kevin returned from the Null Void alongside the Amalgam Kids to confront Ben. Though initially, Kevin was rather by the bodyswap of Charmcaster and Ben.

Kevin, managing to realize just who his target was now, managed to grab the Omnitrix and absorb power from it. However, in the process of doing so, due to some current… complexities, Kevin soon discovered that he had been turned into a girl.

As for Charm-Ben’s hair being fully white. Considering Charmcaster’s Alien Force/Ultimate Alien and Omniverse designs have her hair mainly white, it’s easy to consider that the grey coloring in the original series is simply dye, and the white parts are actual hair coloring. As such, for Charm-Ben, the dye eventually disappeared leaving her with the white hair.