I haven't face a fast wobb, so i might not have the full picture, but Wobb still slow vs common attackers and Set-up Sweepers, if Wobb uses encore then he is risking being 2HKOed, which he is actually sturdy enough to avoid unless SE attacks, but will likely take one mon if this doesn't have a good enough HP
PS: U-turn is actually great as long as you swich to a ghost type poke (not affected by counter), it will remove a big chunk of health and you can't encore it (not easily), volt swich works to, but then you need a dark type to come in, actually, any ghost with good attack or dark pokemon with good SpA should counter Wobb since he can't do anything to them more than encore them (which unless you'r opponent has cobalion, is not really a lost for you)