Using the Research feature, you can translate single words or short phrases by using bilingual dictionaries or translate your entire document by using Web-based machine translation services. To translate text, you may also need to satisfy the operating system requirements for specific languages.
Machine translation is helpful for conveying the basic subject matter of the content and for confirming whether the content is relevant to you. For important or sensitive documents, human translation is recommended, because machine translation may not preserve the full meaning and tone of the text.This provided Outlook Support to using outlook with Excel.
Follows the Steps ..

1. On the Review tab, click Translate.
2. If this is the first time you have used translation services, click OK to install the bilingual dictionaries and enable the translation service through the Research task pane.
3. To change the languages that are used for translation, in the Research task pane, under Translation, select the languages that you want to translate from and to. For example, to translate English to French, click English (U.S.) in the From list and French (France) in the To list.

Note To customize which resources are used for translation, click Translation options, and then select the look-up options that you want.

1. Do one of the following:
   • To translate a specific word, press ALT and click a word. The results appear in the Research task pane under Translation.
   • To translate a short phrase, select the words, press ALT and click the selection. The results appear in the Research task pane under Translation.
   • To translate a word or phrase, type the word or phrase in the Search for box, and then click Start Searching .

Thanks for info.