no
if you're blocking up when the attack hits you'll block it
fuzzies affect your hurtbox, not whether you can block something. a fuzzy is something like a rising jump attack that hits you because you're holding crouch blocking and it hits you while you're standing, because you don't immediately switch to a crouching state from a standing state. it just doesn't matter against 4b.
fuzzy = I was crouching, that move doesn't hit crouchers but I got hit, that's bullshit. Because you got hit before you actually crouched.