Personally, I’d prefer option 3 with an option for the user of doing 4. While I realize that English dominance might be sensitive I’d suggest when doing 3 of putting the English equivalent article link at the top. It’s just a fact that English is globally the largest second language known. I’m assuming now that there are no means to catch user language preferences via cookies or active settings?

BTW, not that the Google Translate API will become a pay for API on December 1st. The Google Translate widget though will remain free. Microsoft’s translate API is also free and seems equally/nearly as good (based on anecdotal evidence).