Perseverance is all you really need to be honest.
What I do is dual wield caestus, use the weapon art then unlock and run behind them while they're doing the L1. Or just use the Mace, Black Knight Sword or Vordts. I understand not every build can use them, but the Mace doesn't have a lot of requirements. If you're STR go Heavy, Quality go Refined. If you're a caster infuse it with Crystal/Lightning/Dark/Chaos and you're set (Mace has good elemental scaling, as well). Pop the weapon art and two swings will break their hyper armor on a heavy armor user, guaranteed. If not it'll take one hit as the Mace has giant poise breaking, or, hyper armor breaking. Never had an issue until I did all of this. The backstab strategy is the best imo but with phantom range and the way these things track? It's hard to get behind them without getting hit.
Just use this every time you encounter them, or launch their *** to infinity and beyond with Stomp. But Perseverance is key to countering them.