Been thinking about buying a kindle for reading Japanese manga, would it work from overseas?

So I live in Australia and want to use a kindle so I can read easier when I'm on my work commute, before I go and make a big purchase, can anyone confirm if they've had success downloading and reading manga from the likes of Amazon JP or Bookwalker JP from overseas. Or even better from Australia? Thanks in advance. I've never had kindle before so not 100% sure if there is any strict region locking bs