fine ill take some time to explain
nightelf-priestess of the moon with owl, put your wood harvesting wisps next to moon wells have auto cast heal on so it will be a pain in the @$$ is he goes for the wisps, if you have a building with low health getting built have all combat units near that so he wont think about it
human-mountainking-storm bolt, get 2 arcane towers near ya peasants so if he goes for them he will have mana drained so he wont windwalk, and having him stunned is good cause his mana is vunrable and it does some nice damage
undead-cryptlord-impale, get a tomb of relics and buy dust of aperance when he attacks something impale him then use dust of aperance so windwalk will only give him a speed bonus, but a nubrian tower will help big time
orc-farseer-far sight, this one is rather harder since its kinda small but orcs have some strength and can realy do quick damage, so you far sight everyimte he wind walks to get some more damage done, also have some towers to make it harder for him, 2 towers preferably so you dont waste money on only towers
so i recon the best to counter this with would be humans since they can completly own his mana