A little macro should be able to handle that for you:
Sub CreateFooters()
'
Dim anySheet As Worksheet
For Each anySheet In Worksheets
With anySheet.PageSetup
.LeftFooter = "Left Part of Footer"
.CenterFooter = "Center Portion of footer"
.RightFooter = "Right part of footer"
End With
Next
End Sub
change the text to whatever you need it to be. If you have special stuff to
put in such as dates, page numbers, etc. Record a macro while doing it to
one sheet and look at how Excel set up that section and copy it into the code
above.
To put this code into action: Open the workbook. Press [Alt]+[F11] to open
the VB Editor, choose Insert | Module in the VB Editor and copy and paste
that code into it. Modify the code as needed for your footer setup.