would a thief of Void have the same powers as a rogue of void but use them for different purposes?

Yes and No. Even two Rogues of Void may not even have the same powers. They have the potential of having the same powers, but Classpect Powers are a big bunch and everyone taps into it differently. Thieves and Rogues have the same verb- But just like two Rogues or two Thieves, there’s a lot of differences to take into account.