Hi Nicccc , as I am an independent MYOB partner I can't answer for the development team.
When multiple currency was added as a feature of the new AccountRight, it took a while, and various feedback, to get originating currency added to the few reports that have that option now. The browser version is the top priority for MYOB at the moment, and is having features added that are not in the desktop app; but multiple currencies is not yet available in the browser (as at 2022.11).
As I said, we can generate item sales reports with originating currency values, and we can mix customers and items in the same report down to gross margin. Email me if you want to know more.