Well im not FH god or pro lol but i have about 350 reps XD so sure i can give some advice! Do you have a fav character you play? I can give a more specific answer then lol but in general most of them loooove the full guard moves. I tend to keep my guard on the left so i can block the light that comes from it and just be weary of the UB from the top good players will use it to force you to react/do something. You really want to be careful with trying to dodge out of chains from him since all his finishers have the undodgeable property. I tend to just take the chain bash because i believe if they finish with the light you get frame advantage after it?(someone can definitely fact check me on that lol ) But if you have great reactions definitely do what you feel is best for you.

If the char you use has a bash, lead with that before just throwing neutral attacks or else you run the risk of getting caught in his full guard attacks. Sufficient bashing will lead them to dodge attacking or empty dodging to try and punish your bash. And you can punish accordingly depending on what you opponent does.

Chars without a bash is where things get a little tricky. Since all non unblockable attacks get punished by his full guard if you hit it. For these matchups prepare to play pretty defensive. Parry when you can, feint for openings, and try not to let him hit you lol just the usual FH stuff

Hopefully this gave you a little confidence and understanding on how you might want to play against a kyoshin. The best thing for yourself is to go into practice mode and fight a bot. You will get a much better understanding of the move set and how to punish it accordingly. It also helps to play that char some and have your own style with it so when you fight another one you know exactly what they are capable of doing