Pikachu's forward-smash is a confusing move to me. Even if I perfect shield it, Pikachu can STILL get away in time. I don't know if it's because perfect shielding likes to push grounded people away from you for some unexcusable reason (it HURTS as Luigi, man ;-;), or it's probably the deceptively short amount of lag after the attack. It's literally twice the length of Pikachu, deals a crap ton of damage, has a sweetspot at the tip of the electricity that actually boasts great knockback, and and it's one of the smash attacks where releasing it makes the move come out quicker than uncharged. But if your character doesn't have good mobility or a super quick punish like Sheik's or Cloud's dash attacks, I don't think you're getting around this move because Pikachu will force you in a situation where you just have to accept the attack, especially when it has stage control. The only way I see is to preemptively challenge it's forward-smash, since the way Pikachu spaces his forward-smash makes him safer, and practically neutral if perfect shielded. This seems to be the same in Ultimate, maybe with a bit more endlag, while its up-smash and... down-smash are nerfed for whatever reason...? I don't know, hopefully with the new perfect shield mechanics, it could be easier to react to and punish accordingly.