QBO not allow to convert currency without home currency, if I create a dummy bank to convert it, how can I settle the rate difference

Hi there, @fordng.

You're correct. When converting currency without the home currency, a dummy account is necessary. There may be a slight difference in the amount when transferring from the dummy account to the foreign account. This amount can be settled manually by creating a journal entry. 

However, it's advisable to seek the advice of an accountant or tax advisor to determine the appropriate accounts to use based on your specific circumstances. This will ensure that the transaction is recorded accurately and in compliance with accounting standards.

You can review this guide to learn how to use the dummy bank account in the home currency to facilitate the movement between two different foreign currencies: Receiving and Making Payment for a Foreign Invoice/ Bill with a Foreign Currency. Although this article is for Singapore, the same idea applies to all regions.

After performing the steps above, you can refer to this article to categorise and match online bank transactions in QuickBooks Online.

I'm also adding these resources for additional information:

• Set up and use multicurrency
• Frequently Asked Questions about Home Currency Adjustments

Feel free to reply to this post if you have further questions about handling multi-currencies. I'll be happy to lend a hand. Have a good one!