The correct response to Chevron being overturned is for every single environmental group to start filing millions of lawsuits, right now, today, arguing that various regulatory decisions didn't go far enough.
Absolutely flood the zone.
Just take every public comment period submission by Greenpeace or Ducks Unlimited or literally any one that the EPA hasn't fully implemented and demand the courts rule.
File everything in the 9th circuit.
Play their game.
Fundraising is the linchpin to this scenario because NGOs simply cannot outspend corporations. David and Goliath asymmetry in regard to legal budgets. How do you craft that message to sustain the flood of suits?
Or you find a lawyer in the Ninth Circuit with a degree in Environmental Science and a whole lot of time who doesn’t mind waiting to get paid. Either one, really.