Or maybe find a worthy Muggleborn in a country that didn't identify Muggleborn children, and tell them some extensive lies, fake up a surrounding story and corresponding evidence, so that, from the very beginning, they'd have a different idea of what magic could do.

Pretty sure this is Jean-Jacques Rousseau's strategy in Emile. Albeit for social-sexual development, instead of magic.

Hi, I'm visiting Australia for the weekend. I'm not so enthusiastic about the drinking but the rational conversation sounds great. Is it ok if I drop by?