When Undine generates a copy of Undine it will always have max stats equal to the original copy. Meaning, despite the fact that the copy will be spawned with current health equal to the damage the original took, it can still heal up to the original's max.
And no, hitting it with Antimatter and then damaging it will not create a copy with inverted attack.
The trick here is that I don't want to be biased towards negative statuses. If statuses affect copies, all statuses should affect them, and if none do, none will. It is why I believe even having adrenaline transfer over, at the base attack of 2 should be fairly balanced. This is considering that in order for copies with adrenaline to be generated, the original will already have to be damaged, and depending on by how much, the spawn could already be quite squishy.
I'll be putting the new versions in the OP.