Although EU versions have 2ml it’s not policed. if you look on vaping sites then you will find plenty of tanks with much bigger capacities! I reviewed for over 6 years and always got the international (bigger tank versions sent) not once was there an issue with customs over the regulations.
You get much better choice with rebuildable’ s over stock coil tanks.
Even with 2ml tanks most will have a bubble glass available which usually doubles capacity, and even with the regulations (if they were policed) it only applies to the sale of the fully assembled tank so it isn’t against regulations to sell larger capacity glass tubes or extension kits. Some manufacturers consider they are following the regulations by having a 2ml capacity assembled tank but then including a bigger glass in the box.