Whoa! A remake of one of my fave games of all time!
While I could instantly tell it was Shion, I think your style lacks a bit of the cutesy of the original. Then again, this happens to pretty much all remakes, since cuteness doesn't sell as well as coolness these days. Under these circumstances, I think you've done a great job on modernising him.
Have to say your walk animation is pretty bad. (Sorry) While you made sure his body bounced, (instead of just the legs like in the original) the legs is just poorly done. I could accept this on a 8-bit game but not 16-bit. His legs are very well animated in the original game, so study it more (it's easy to find sprite sheets) Oh, what the heck, here's a comparision:
Take the good parts of these two, mix them up, and you'll have a really good 4-frame walk.
I like how you switched the hands on the shield and sword. This way he has a much better range, and you have to push a button to parry arrows. I think the sword slash could need some more work. As for the idle animation, I personally prefer a breathing animation instead of blinking eyes, but that varies from person to person.
Love the big psycho mushroom! Can't wait to see more of this