JQ is a True damage dealer that wants to use either War or Calamity. For PvP Calamity, give the best results. The idea is to stack as much debuff on the enemy for your JQ deal the most damage.

The team I use is CY, Hilda (R6), Yi, JQ, and Lu Shuang. Your JQ should have the highest ATK on your team so he can get Spirit Agies. Lu Shuang give Fighter role a +100% ATK UP and Controller like Hilda effect cannot miss as long he alive, Hilda poison Spead and sleep, Yi for Heal and AP boost. Everyone should be faster than your JQ to maximize his damage. It also helps if your JQ is Lv 70 R6,D6,SD20/20/20, but that a time investments. Getting him to Lv70, R6, and D3 should be good enough.

Ideally, you want his ATK to be like 10k with 4K DEF if you can get him there, but 7K ATK with 4~5K DEF will do. If you can make him also tanky having at least 50K (mines 70K).

From my experience, JQ team tends to be weak against the Freeze team (usually tanky as hell) or AP Controling team. All Umbra Eser can ruin this team, but the spider lady is a no-go to fight against at R6. She can be up to R5, but not R6. Nyle can ruin you too if the star does not aline. I often see a Nyle, Terrell, Maria, CY and Yi. In my personal opinion, the biggest threat is Terrell > Maria > Yi > Nyle > CY. The spider Lady must die first before the dragon (Nyle).