You can do literally anything once you've read an air-dodge. If you are both off-stage, dair spike is the way to go. It doesn't require as much precision as a sweet-spot knee, and even the non-meteor hitbox of the dair is still very strong. Other than that, knees are the way to go if you can land the sweetspot consistently enough. Otherwise, an upair is fine. It's not as optimal anymore after the nerf, but it's still good. Off-stage bair punishes are actually pretty good too. Falcon Punch is fine, but the problem is that Falcon Punch is actually kind of weak, and I'm pretty sure the start-up on Falcon Punch is slower than most air-dodges, especially if you opt for a reverse punch. The point is, you have a lot of options to heavily punish air-dodges. But the best way to punish them is the knee, in my opinion. Experiment and find out what punisher works best for you.