I can answer this for SAS Enterprise Guide.
First, you must have the Spanish language resources installed for SAS Enterprise Guide. In the SAS Enterprise Guide installation folder, you would see a folder for "./es" installed with the application files.
With this in place, you will see a "Spanish" option under the list of languages in Tools->Options, General tab. Select Spanish and restart SAS Enterprise Guide to see the UI in Spanish.

If you don't have the Spanish resources installed but you want the UI to adhere to Spanish conventions for date values and other cultural differences, see the advice in this blog post.
Chris