I'm here to share with you a few information and help you with your home currency, kudosleb.
You can only change your home currency once you have not activated the Multicurrency feature in QuickBooks Online. To do this, you can follow the steps below.
If you have already activated the Multicurrency feature, you can only change the home currency by deleting all your data and starting over from scratch.
Changing home currencies may affect previous reports or transactions since this needs to recalculated and adjusted based on a new rate. For your reference, you can read this article for additional information: Enter A Home Currency Adjustments For Your Foreign Balances.
Reach out to us if there's anything else you need about home currency. We'll always be around to help you at any time.