I do enjoy some of coldplays stuff, there could be potential. But knowing Gaga and how she chooses her duets now on albums this will probably never happen.
I don't really like Coldplay, I rather dislike them tbh. Moreover, Gaga is way more talented, in my opinion. She'd be doing them a huge favour if she decided to collab with them. BUT I am all for Gaga collaborating with David Bowie! That would be absolutely fantastic!