Midjourney accepts payments exclusively in US Dollars (USD).
If you're paying with a currency other than USD, your bank will automatically convert your payment to USD. This process will involve your bank's conversion rates, and depending on your account terms, they may also charge a foreign transaction fee.
Please note that Midjourney has no control over the conversion rates or any bank fees applied. If you have questions concerning how your bank manages foreign transactions, it's a good idea to contact them before subscribing to understand what to expect.