This policy setting sets the "Show Paste Options button when content is pasted" option found under File tab | Options | Advanced ...

This policy setting sets the "Show Paste Options button when content is pasted" option found under File tab | Options | Advanced | Cut, copy, and paste options.

If you enable or do not configure this policy setting, Excel will show the Paste Options button after inserting cells, rows, or columns that contain formatting. This is the default behavior.

If you disable this policy setting, Excel will not display the Paste Options buttons on insert.