Personally I would prefer to call it "Roscosmos/ESA connects..." than "Russia/Europe connects". It adds information for free while keeping it short, just put it in the title. ESA is more specific than Europe or EU, so why make the title more generic and opaque than needed? It tells you it's not a random team of "Europeans", it's not an amateur hacker in the backyard, or some intelligence agency.
The expansion isn't really needed when it's a "household name" in the field. If you read a title about space industry there's no need to expand or explain NASA, ESA, Roscosmos, maybe not even for ISRO or JAXA, although I can see how some of these wouldn't be the most familiar for people in the West even when they have some interest in space news.
The expansion isn't really needed when it's a "household name" in the field. If you read a title about space industry there's no need to expand or explain NASA, ESA, Roscosmos, maybe not even for ISRO or JAXA, although I can see how some of these wouldn't be the most familiar for people in the West even when they have some interest in space news.