Zameer here from the Shopify Developer Experience team.
It seems as though you are passing in an array for the price field on the line_items parameter. As per our documentation, a monetary value string is expected here, not hash. When a `variant_id` is provided, the price field is ignored as it is just retrieved from the variant itself.
I also see that you're trying to pass a currency value, unfortunately, multi-currency functionality is not currently available for draft orders. You'll have to create orders directly if you're trying to use the new multi-currency feature.