To do Alt + A O on Mac in Excel, download and install Accelerator Keys, then press Option, followed by A, O.
Command: Queries & Connections
This is how to do Alt + A O on Mac in Excel with Accelerator Keys, the native ribbon and alt key shortcut solution for Mac users who get more done with Excel.
Alt + A O opens the Queries & Connections pane. This sidebar displays all Power Query queries and data connections in your workbook, allowing you to manage, edit, refresh, and monitor your data sources from one central location.