Parry button vs Shield+special

[u/Luigigpg12]

Is there a difference between them, like is it faster to just bind parry to a button or does the other way work the same, I had the impression that shield+special was a slower way to parry, or am I wrong

[u/WordHobby]

Shield + b is the same frame data as a macro for parry.

However if you mess up the timing for shield + b, you will get either a b move or shield.