we don't have a program for non profit organizations, however, if you create a template on the Composer with a latest posts block set to retrieve the last published posts, you'll end up with a ready to send template which you can send manually whenever you'd like to.
I understand. Unfortunately we don't fully support multilanguages environments. I'd suggest you to do the following: create different newsletter templates, one for each language you need. The only block you'd need to recreate manually is the legal block. Then, you can use those two templates to target english speaking and spanish speaking subscribers (if they belong to different lists). At the moment, targeting can NOT be saved in a template, so you should select it manually every time.