what you can do is to add some transcribe variables so you can generate language codes.
make on like transcribe_lang_country with the value "en" and one like transcribe_lang_language with the value "US" (this is for the american english language version. I don't know the spanish ones)
then let the locale be determined by the browser by adding the country variable to the html:
<html class="no-js" lang="{transcribe_lang_country}">
This would let the browser render the time notation in the proper format.
Mind you; EE wil render the date notation based upon the language settings of the logged in user. So to check if it works use another browser where you are not logged in.
Another nice little trick is when you are using validationengine on your forms you can get the error messages easily in the proper language by calling the right locale {transcribe_lang_country}_{transcribe_lang_language}, which will render as en_US
there is also the date/time convert addon from Carl Crawley that could help: http://devot-ee.com/add-ons/date-time-language-converter