Can I write a purchase order in a different currency?

Greetings, @dtsiang.

Thanks for reaching out to the Community. I’m here to share a few details about creating a purchase order in a different currency in QuickBooks Online.

Yes, you can write and use a purchase order to buy items in a different currency once Multicurrency is turned on. However, you won’t be able to change the currency vendors with existing transactions use. What you need to do is add a foreign vendor.

Here’s how:
1.    Go to Expenses from the left panel and select Vendors.
2.    Click on New vendor button and enter the vendor information.
3.    On I pay this vendor with drop-down, select the appropriate currency.
4.    Once done, hit Save. (Attached screenshots)

Now, to create a purchase order for this vendor, follow the steps below:
1.    Go to the Plus (+) icon and select Purchase Order.
2.    From the Vendor (Choose a vendor) drop-down, select the newly added vendor.
3.    Enter necessary information.
4.    Click on Save.

For more information about adding a foreign vendor with their corresponding currency, refer to this article: https://quickbooks.intuit.com/community/Income-and-expenses/How-to-add-foreign-vendors-with-their-corresponding-currency/m-p/186244.

That should get you pointed in the right direction. Should you have any follow-up questions, don’t hesitate to let me know. I’m always here to help. Take care and have a good day!