What would be the best egg substitute (or combination of subs) for this recipe? Thank you!

In this recipe, the egg is used as a binder, so I think your best egg substitute would be aquafaba, the drained liquid from canned or cooked chickpeas. You'll need 3 tablespoons for each egg, and you should whip it just till foamy before adding it to the batter. Here’s a Food52 article about egg substitutes: https://food52.com/blog/24554-best-egg-substitutes