I'll show you how you can import your GL to QuickBooks Desktop.
QuickBooks Online exports the General Ledger report as an Excel file. To import it to QuickBooks Desktop, you'll want to convert the Excel format to an .IIF file. You can look for conversion services online that can do this.
Before importing the IIF file (after converting), I'd recommend making a backup copy of your company file first. Next, switch to single user mode by clicking the File menu, then selecting Switch to Single-usermode.
To start the import process:
Go to the File menu, then hover your mouse on Utilities.
Choose Import, then select IIF files.
Click the Import IIF button, then browse for the converted IIF file.