Hello there, @castagnoli.
I want to ensure customers like you are having the best possible experience while working with QuickBooks. We're aware of the feature you're looking for about importing budgets prepared in Excel to QuickBooks Online (QBO). However, this feature isn't available in QBO as of now.
As a workaround, you can look for a third-party application that can handle budgeting through our App Center.
To learn more about creating, editing, and managing budgets in QBO, you may check this article: How to create, edit, and manage budgets.
You can always add a post/comment below if you have any other questions about budget. I'll be always here to help you!