Oh it's SELF Anthem, well that changes things. Theoretically, GV can continue to spam Prevasion by continously recharging, nothing prevents him from doing that, even HF Blade won't be able to destabilize what essentially is already disordered elementary particles, but it does shrink the electron cloud (possible places of where electrons can be in an atom), however, since GV is pure electrons, I'm not sure if it would work.
Raiden does have the stealthing, I'll give you that, but GV is only attracted by magnetism when he's using the Flashfield specifically, this is pretty much proven except for again, Quasar Collapse. In this situation, GV won't be using his Flashfield at all anyways, or else he's screwed. At the same time, using Flashfield is in character if he manages to get three tags in...
Even if he stalls with Prevasion, Raiden has the Stamina advantage, meaning that GV will get tired first and pretty much lose there