you can act from the first frame of drop when you powershield something.
if tornado is done correctly it hits every 4 frames If I remember correctly.
when you don't mash B hard it hit's every six frames. (if done frame perfectly frame 6 grabs will trade but you will still grab)
if the tornado is fresh you will have 5 frames of shield stun so it's practically impossible to do something in that case.
I would not challenge it :/
I don't know the downB frame data but perhaps that move would be a better idea because of invincible frames
if tornado is done correctly it hits every 4 frames If I remember correctly.
when you don't mash B hard it hit's every six frames. (if done frame perfectly frame 6 grabs will trade but you will still grab)
if the tornado is fresh you will have 5 frames of shield stun so it's practically impossible to do something in that case.
I would not challenge it :/
I don't know the downB frame data but perhaps that move would be a better idea because of invincible frames