If nothing else, I'm admittedly a little rusty on older chapters, but while I can see the Gauntlet 'siphoning' off Void magic from Louise to use as power (and thus, Louise 'becoming' a super-powerful wind mage in the interim), I'm somewhat raising an eyebrow at it having the ability to lift the 'Void' wholesale out of Louise, and placing it into Eleanore.
Obviously, things happen as they must, but again, while I'm not overly (or incessantly) familiar with Overlord-style magic limitations, this feels a bit out there that the Gauntlet could suck up the Void wholesale, wrap it in a bow, then 'gift' it to Eleanore in such a way that still results in Louise having plenty-powerful magic abilities afterwards, even if they are unicorn-boosted or what have you.
Some of the Void remaining in the Gauntlet due to its ability as a magic receptacle, sure - and maybe that's all it is. Just feels a little odd (though admittedly somewhat less so due to the 'bigger fish' aspect of the Evil Cabal and the Hell dimension and such) if it's more 'permanent' in such a fashion.