eh ill asnswer this question for you through my own experience so take it how you will:
valk, hes slow (in human form) good damage (in human form) and a few little mind games here and there.
in human form: watch out for his 6C, imo it feels fast. it cancels from 5C, and 2C. usuaully you just block low, so REACT to this overhead, do not expect it.
his strum wolf DD has more loose holes than a 5 cent hooker. you can easily 5D the the DD on start up or very late use 2D or 6D. if you are in the air late chain jD>jD to counter the second blow. 2D and 6D work if you block the first hit. afterwards just if you didnt counter this yet, IB the rest of the DD until just before the last kick, then 2D,6D into whatever, if you IBed you should have at least 2 stars. vs his Air DD jD,5D<and 6D kills it.
he has very long pokes, so only use 4C at near max distance, or they can IB it and respond with a 5B CH (bad for you) into a deadly combo. imo his pokes feel fast as well so dont 3C at close range. also beware of his 2C, it is a legit anti air and i myself have no problems AAing an IAD happy haku. 6A can also be "counted" as an AA due to its auto-guard. his pokes are slow enough to IB easily, but it puts you in so much block stun that its hard to counter between say : 5B>2B>5B>5C. its legit and cannot be countered so wait for a good opportunity.
his strum wolf DD can easily be used as a reversal, kinda like daifunka just not with the insane invincibilty, it has good invincibilty, and if you are not careful or being careless with 2A,5A,4C poking you will eat it if they choose to use it. his air DD is terrible outside of combos and quite easy to block. butt his damage isnt something to be laughed at, one wrong move and you lose 5-7k hp.
his jC is also something to watch out for, it feels faster than our jC. also beware FC 6C.
in wolf form: the damage is minor. tsubaki level. but his wolf form isnt ment for damage, its ment for the insane amount of heat he gets per hit/block from wolf cannon. the command grab is strong but a quick 2A,jA depending on your current position knocks him out of wolf form. in wolf form his A is a solid low, his B is a mid/high also air unblockable so barrier. his wolf C can be dangerous because he can immediately dash at you the revert into human form and do w/e so be a bit on guard.
all in all this match up imo goes around you being careful with your moves: his shoulder rush specail is +2 on block so dont try to mash out, just relax and be patient.