I signed up via the Australian website. I bought an item from an Australian seller in the app which showed me the purchase was in Australian dollars. Long story short I got charged extra. Turned out the fabulous UX/UI on the websitr had set my default transaction currency to USD even though the app was showing me everything was in AUD.
Etsy support were crap. They were basically saying it was my fault I didn't know about their stupid default currency setting which is hidden on some obscure tab in the user setup when you go in via the website.
They offered me a gift certificat as I'd that was going to make the additional currency conversion fees and my lack of confidence in the product go away.
Don't do it too yourself. If you want to shop local go local.