I haven’t known of any recently, but I’m not really in the RP-PvP loop. There are some RP-PvPers in the Ashen Court, and there was a bit of discussion about organizing RP-PvP events or campaigns a while back, but none have been as of yet. I think some could be, but the Ashen Court’s thematic focus is fairly narrow.
I’d recommend a military RP/RP-PvP focused Discord if I knew of one, but like I said, I’m not in the loop. I hope you find something!