There is when you want to consolidate lots of Excel files or an Excel file containing many sheets in one sheet. (Of course, if you translate Excel files using SDL Trados or other CAT tools, you can count the words of all Excel worksheets or workbooks.)
I found a very useful VBA file which consolidates all worksheets or workbooks. This VBA consolidates 1) data distributed in Excel worksheets, and also 2) data distributed in workbooks in one workbook (sheet). It's also possible to specify sheets you want to include by entering, for example, "1,3-6" in the bottom left field in Figure 1. You can directly download it by clicking this link (the Project Password for the attached file is "1111.") [File removed]
The user interface language of this tool is Korean. If you are familiar with editing .vba file, you might be able to localize the UIs. You can find more information at this blog.