You are asking for CC resistance and Fetter Ward

CC resistance and Fetter Ward worked on the following:
- Stun
- Silence
- Sleep
- Bind
- Heavy
- Knockback/Draw-In (same CC type)

prior to patch 6.1. While for Crystalline Conflict it may not be a good choice to bring back CC resistance, Frontlines and Rival Wings are a whole different beast given player count. Either or both need to return, with priority on large-scale-PvP CC resist after having suffered the effect previously.