Temporary state shield

[Junane]

I'm trying to create an effect similar to Final Fantasy 14's The Warden's Paean as pictured below

I can manage the first part with Yanfly's State Category plugin but the next part is a bit complicated. If there is no "debuff" (as I've defined by the aforementioned plugin), it will give the target a new state which should block the debuff category for 1 effect then be removed. However, regardless of what I've tried, a scorpion with +100% Poison rate will still bypass the state shield with normal attacks and neither the poison or shield states will be removed. Can this be recified somehow?

 

[Jules98]

By any chance, is the attack the scorpion uses a certain hit? Certain hit attacks will apply their states even if the target has a state rate of 0% against that particular state (state resist is not bypassed, however).

 

[Junane]

By any chance, is the attack the scorpion uses a certain hit? Certain hit attacks will apply their states even if the target has a state rate of 0% against that particular state (state resist is not bypassed, however).

It uses the Attack skill normally defaulted in a fresh project, so the attack is a Physical Hit.