This has nothing to do with Brexit and I am not even sure this is the right place to ask this question. I recently bought an electrical appliance from a Web store with the .eu domain extension, only to realize after it arrived that it has a UK power adapter. Nowhere on the product page was it mentioned that it was coming with a UK power adapter. After contacting their support about it, they replied that they mention in their Terms & Conditions page that all products are conforming to rules and regulations for the UK market. That page is the only place where they mention this. Their FAQ doesn't mention anything about it.
And my question is, aren't there any legal implications for the products of a Web shop with the .eu domain to conform to EU standards?