Mike
WordPress and BuddyPress are set up to work in different languages provided the alternative language files are available and installed.
There is a difference between running a site purely in another language, vs. having an existing site be able to switch between languages.
If the site will be purely in Spanish that’s straightforward, you have to just load the WordPress and BuddyPress Spanish language files. If you want to switch that’s more complicated and you will want to use a plug-in to achieve that.
If you are switching between languages, there’s the question of the WordPress & BuddyPress text (the buttons, things like “user1 posted an update 10 minutes ago” etc., and then there is your content, your words and the page, the menus etc.
You’ve got a bit of reading to do to learn more about this.
Start with https://codex.wordpress.org/WordPress_in_Your_Language
For BuddyPress you can use this plug-in to make sure it loads the latest Spanish language files:
https://wordpress.org/extend/plugins/buddypress-translations
There are a bunch of plugins for maintaining a bilingual site that all work in different ways. Try WPML or qTranslate to get you started (although you may find they do not fully support BuddyPress, you’ll have to try them or contact the developers to see.)
TL:DR; is it’s very straightforward for standalone sites in a different language, but pretty complex for multi-lingual sites that you can switch between languages.
