I would recommend that EU holds Vietnam farmed omnivorous vannamei shrimp to same import duties (tax rate) as all other countries for a non endemic commodity grown vannamei.
I would recommend only zero duty rate for vannamei shrimp from countries where vannamei shrimp is endemic.
Of course farmed carnivorous Black Tiger (Monodon shrimp) – is native to Vietnam so should get zero duty on that shrimp into EU. Great market opportunity. Focus commodity vannamei USA and larger BT mondon to EU and Japan. India is already strong in EU/UK.
Otherwise we will start seeing market distortions what with Europe being the world’s largest consumer.
BTW….the 0% duty rate offered on farmed shrimp from Vietnam into EU was said to be a trade off for better IUU fishing compliance, regulation implementation and general crackdown on illicit practices disallowed in EU – and by extension their long value chain. But used now to spurn Vietnamese to battle India in the Shrimp Wars.