Good evening, @leoma_armstrong-.
Thanks for posting your question here. Allow me to share some information about changing currency.
At this time, QuickBooks Self-Employed doesn't offer a feature that changes the currency. I'm going to submit feedback to our Product Development Team to review and consider making this an option.
In the meantime, you can check out our QuickBooks Blog to learn more about new features being added every month.
Feel free to comment below if you have any more questions or concerns. I'm always here to lend a hand and help. Have a good weekend!