PerlMonks is not a code writing service. You cannot simply give a requirement and say "please send teh codez".

Keeping that in mind, what you will get here are suggestions for what CPAN modules might be relevant to your needs

If you have an Excel file, you can use Spreadsheet::ParseExcel to read in the data. Once you have it, you can use WWW::Mechanize to send the data in the cell to Babelfish to accomplish the translation. Once you have the data back (retrieved using the WWW::Mechanize API), you can store it in a file using Spreadsheet::WriteExcel.

So, you have many small pieces you can work on independently:

1. Reading in data from Excel (although just saving as CSV and using Text::CSV would be easier)
2. Taking a string in one language and submitting via HTTP using WWW::Mechanize to Babelfish
3. Getting that result string and saving it back to Excel using Spreadsheet::WriteExcel (although CSV again would be easier)

The monks here will be happy to help if you have source code that you've tried to get working and can't. Just remember to heed the advice in How do I post a question effectively?