After some brainstorming with
darksylvion, we came up with some ideas to counter Kang + Bronzong. Well yes, you can make Bronzong's Hypnosis ineffective with Electric Terrain and Misty Terrain, but the opponent can alway send their own terrain setter or simply use Trick Room to their offensive advantage. To prevent such scenarios from occurring, your best interest (imao) is to never let Bronzong use Trick Room in the first place. Here are some strategies that we talked about:
1. First, you need to prevent Kang's Fake Out from being effective. The easiest way to do this is having Tapu Lele on the field. Other methods include the use of faster Fake Out users or faster Quick Guard users. Based on experience, a faster Kang is definitely effective. However, I'm not too sure about the viability of potential Quick Guard users; examples include Terrakion and Keldeo.
2. The next step is to eliminate or remove Zong for good. Bronzong's Abilities (Levitate and Heatproof) are truly troublesome, but a combination of effective moves (Ex. Tapu Lele's Shadow Ball + Volcarona's Inferno Overdrive) will take out Bronzong. LO-boosted Hyperspace Fury and Aegislash's Never-Ending Nightmare also OHKO Bronzong. There are also the "unhealthy" methods of using Roar, etc. The possibilities are dedicated, but limitless.
Matame and
miltankmilk also made good points about Bronzong, too, but I personally don't want to wait out TR for 5 turns. Also, I agree that Hoopa-U is the true threat in Trick Room. It's even effective in Tailwind and through Z-Ally Switch (lol). However, it is only threatening when the speed is in its favor. Again, in order to avoid such issues, carefully prevent them from occurring (just like how I discussed with Bronzong). I'm not sure if this post helped or not, but I nevertheless hope that it encourages players to learn how to adapt to the ever-changing meta. Seriously though, Trick Room is a playstyle that every team should be prepared to go against.