Hi,
Yes, should be from Excel, when you select 2 sheets to print it will print duplex. Same as you print the whole workbook. The worse case, copy and paste to a different worksheet then print.
Updated: Just have a quick test, Excel won't allow we select 2 areas on 2 different worksheets. When I select the second area, it selects the whole worksheet, not a small area. I have to do plan B: copy & paste.
Regards.