So, the way I see this is that all Cobalt really needs to do is land a few really strong hits with plutonium dissipation in mind (easier said than done ofc). At Max Aura, the natural effect of dissipation is much stronger than normal, which is why she could delete High-Mid with one blow later against Marx. Similarly to the fight vs Asuna, Cobalt would be discovering deeper parts of her power through this fight depending on how hard Javen will be resisting here. This means that the dissipation would eventually work since the limit of what it actually does can’t go beyond High regen, which is what Javen has (Low-Godly over time, but I’m not sure if it’s combat applicable. If it is dissipation would still be a very major thorn in his side as his regen slows way down).
Javen’s intellect is just gifted and Cobalt’s is extraordinary genius, so like with Asuna cobalt has an extreme advantage when it ones to planning here, although this is far more important considering Javen doesn’t have any precog or danger sense equivalent which would counter it. So as far as his imagination goes, while extremely impressive, Cobalt is gonna figure it out eventually and plan around that. He won’t be able to imagine the stuff away once she hits him at point blank range all the time. He doesn’t appear to have a way to see through her tricky methods either such as plutonium bend and generating fake energy signatures. And of course the stat difference means every landed attack basically obliterates Javen so his willpower would only work so much, considering that kind of injury can’t be survived on willpower alone in conventional circumstances. Because of this, I think Cobalt has a pretty good advantage and would be the likely winner over the course of the fight, but I’ll hold off on voting to see what Javen has to say next