The Nox PvP in Silent Knights was her vs Jairx. They were technically holding back though, using their ordinary swords and stuff. And they just did it for fun. But they didn't just do in rp, they actually rollled and stuff like it's a normal battle.

The other 'PvP' was in meaning of madness. Which was technically not a PvP lol. Nox was controlled by the violet as an effect and she attacked the other party members. They joked about how Nox almost killed the others during fanart feature.

The other one was in Strange Roads which was in the finale episode. It was Nox vs the final boss battle. Not to spoil anything more but it great and probably the most heroic/anime thing Nox did on stream.

With Mimika's other character, I've heard she had a PvP in wicked ways but I haven't finished watching that yet so I'm not really sure.