How to modify a field value at theme/Views level? My content type has a Link field which stores a website URL (e.g. 'site.com'). I use this field in various views and node templates.

My site is multi-language, and I know how to check the current language using the global $language. 

Now I need to modify the link field value depending on the selected language. So output 'site-en.com' if visitor is viewing the site in English, 'site-de.com' if viewing in German etc.

I can't use manual field translation (Entity Translation) because the field values are imported from XML using Feeds, and there are hundreds of values.

So I wonder if there is a hook to programatically modify a field value before it is used by templates and Views module?

Or maybe there is a better way..?
copy /modules/field/theme/field.tpl.php to your theme folder and rename it to field--field-site-link.tpl.php (if field key of your field is field_site_link), edit template, see comment in file for avalable variables, or just override existings