He is currently weak as a Jungler (the role he was balanced as) since he depends on early game ganks and mid game to transition to a somewhat good late game. He is a heavy ganker jungler but since his clears and sustain are quite poor he struggles if there are no target to gank becoming close to useless late game besides a ult on 3 people before blowing up in 0.5 sec without killing anyone.
Top laner he is decent, problem is current top laners has a way to either force trades with close to limitless resources or have a way to sustain in lane to survive the poke due to being unable to get into trades as often (Top lane currently is heavily trade reliable). Wukong has limited resources early game with his low mana pool and high costs, that in addition with no in-built sustain leave you with a way of playing him similar to Pantheon, depending only in his early game to be able to be threat late game, there are variety of champions that re better at doing so.