>>43749463I think it's playing off of original Slowking's shtick of "unlocking" various latent bodily functions due to poisonous fluid having a chemical reaction.
Like Slowking's brain to become super smart, where as G-Slowbro has near instant reaction timing from the constant injections affecting its limbs, except it's way more potent due to the spiciness of G-Slowpoke's diet.
Which potentially explains why the reason K-Slowbro doesn't feel anything major despite the same type of bites is because its tail is the longest distance for fluids to travel (as well as being detachable) so it's more or less numbing agent than anything.