The more I think about it, the more weird this whole new VAT regulation seems.
Let's just say, for the sake of this example, that you browse the internet and find a seller of hand made boutique t-shirts. The shop is in Netherlands. T-shirts are 20 euro each incl. Dutch VAT. You buy five of them, click on shopping cart, shipping is added, you pay via paypal and off you go.
Meanwhile in Netherlands some shop owner just received their first order in 2021 from UK. And after packing the t-shirts into box and ordering delivery via pakket2gaan our Dutch entrepreneur discovers that in order to get it collected by the courier he has to fill out a new mandatory form to go with the shipping. But this time, unlike shipping to US or any other country outside of EU - it's not a customs form, it's an additional VAT declaration. And on that declaration he's required to write down things he never ever had to put on any customs form or shipping manifest to any country on the planet ever - a VAT number that doesn't belong to his national tax office and EORI number issued by foreign tax office that's no longer part of the "E" in EORI.
Confused and perplexed Dutch seller gets on the phone to his accountant and discovers that a foreign government of an island just outside of Europe since last Friday usurp a right to profit off his hard Dutch handy work and requires him to hand over his bank details for direct debits and register for VAT.
What's even more bizarre, the Customary Revenues of Majestical Heirs, or some such thing from a far away land, demands of him to become tax a collector in-situ on behalf of the Head Tightwad of Borissian Isles' treasury. His first task is to call his British customer and retrospectively demand additional levy of 4 euros on each T-shirt, only for the purpose of transferring it back to the Kingdom of Uniteds coffers via swift. "Because this individual on your server belongs to us, so we'll need you to kindly Dick Turpin his four letters on our behalf and then send us sack of his money. Thank you for your honesty, cooperation and respect" reads the short version of the legislation on the web.
And his second task of 2021 is to rebuild his website, shopping cart and merchant backend in such a manner that it automatically adds 20% impost on his Dutch products if any of them get ordered by someone living up to 500km east of Ireland.
The way I see it, there are three reactions/options.
One option is to say "**** it, that's just mad", cancel the order and never make a mistake of letting UK customer onto your websites and servers ever again.
Second option is to follow the procedure to the letter.
Third option is to realise that any opportunistic backwater country brave enough to ask a stranger like YOU to do their tax collecting must be disorganised and really short on resources plus - they have absolutely no jurisdiction over your EU business and they literally just resigned from participation in European courts.
So you grab that form, stick it on 100 euro worth of packed t-shirts and write:
Net value of product: 10 cents
UK VAT: 2 cents
Delivery: 99.90 euros
Contents: Biological waste for testing
UK VAT number: GB11223344
EORI: yomama
And ship it out with tracking number. It's not your problem, let the customer track it and enquire to border control about it. HMRC doesn't own you abroad, you just bin their letters if they ever arrive.
But I guess the main question is - what would YOU do, if you were selling stuff over the internet and some Principality of World's End wanted you to register for their irrelevant local taxes and levies if you shipped your product to their country?