Joiin automatically imports Xero Tracking Category and QuickBooks Class data from Xero/QuickBooks so it's easy to get a consolidated breakdown by Category/Class.
To do this on the Profit & Loss Report simply select the Compare by Tracking Category/Class option as show below.
If you have Xero companies selected you will then be able to select the Tracking Category, such as Cost Centre or Region, you wish to report on from the Categories dropdown.
Then simply click the Run report button to run your report and you will see the P&L broken down by the selected category, with the category options in columns. For example broken down by Region as in the example below - with a Total column showing the consolidated total.