I know, but according to official merch etc igirisu can mean England as well. I've seen stuff where they use the Union Jack, 'igirisu' and then England written in English :/ Which is completely inaccurate. And potentially offensive to people from Wales, Scotland or Northern Ireland. Himaruya also refers to him as England on a number or occasions and in the England vs Liechtenstein strip he is wearing the England football kit and there are England flags in the background.

Even if he acts as the UK/represents it doesn't mean that he is the UK.

Yes, there is a stereotypical one, and yes it is exactly the same as a stereotypical English accent XD In reality there is no such thing, though.