However, the scenario this will lead to is: Industry will still leave high-energy-price areas. If low-energy-price regions can be found within the EU, industry might go there. Otherwise industry will be off to wherever in the world is cheap and happily charge the EU carbon import duties to EU customers. The rest of the world will enjoy low-priced not-carbon-neutral products that the EU will never be able to compete with because of economies of scale.
The only viable ways out of this isn't import duties but import restrictions, i.e. outright preventing goods that are not up to EU CO_2 standards from being imported. That will lead to local CO_2-neutral industries that have to be continuously walled off, because if they are exposed to the rest of the world they will be too small and expensive. The other way is a global agreement on CO_2 standards, such that those kinds of import regulations are unnecessary.