Just go to the Tools menu and choose Customize Keyboard. You can now assign your own key combinations to many commands within Excel. It should show up for everyone else (in the non-Insider update) sometime next month. If you were waiting for this feature so you could upgrade from Excel 2011, now you can. If you have version 16.17 (180822) or greater, you should To get the update, go to Help > Check for Updates, and opt into the Insiders program and choose the Fast updates. The 'Customize Keyboard' feature is now available. There's a feature in the latest Insider Fast update of Excel for Mac that