I understand your reluctance to even suggest a link. Tonally, the two movies couldn't be further apart. In fact, it seems like the similarities are just chance, with a bit of help from storytelling stereotypes.
I assume the similarities you refer to are based around the fact that the main female characters in both "Two Weeks Notice" (2002) and "A Most Wanted Man" (2014) are crusading lawyers working for charitable agencies who become the inappropriate object of affection of a cynical rich guy -- an affection that drives at least some of the film's plot.
Put like that, they sound like the exact same movie, except that one plays it for light laughs and the other for grim thrills.
In short, the two have no direct link: "A Most Wanted Man" was released 12 years after "Two Weeks Notice," but it was based on a novel by the great spy-fiction author John le Carré, written in 2008 (still later, but not as much). Le Carré wasn't the sort of guy to plagiarize, and he certainly didn't give any credit to "Two Weeks Notice" in the book's acknowledgements.
Instead, he credits the lawyer character (or at least her fictional charity, Sanctuary North) to real-life journalist Carla Hornstein, who really was trying to help a wrongly detained Muslim man living in Hamburg, Germany.
It's likely she became a lawyer instead of a journalist because the crusading lawyer is a stereotype we're all familiar with and le Carré wouldn't have to spend as much time explaining her motivations (the book is a classically twisting spy thriller, so he needed to save pages for plotting).
You know it's familiar because rom-coms like "Two Weeks Notice" thrive on character stereotypes for basically the same reason: to economize on character development so they can go straight to the comedic misunderstandings and hijinks.
As for the bond of affection between the two separate rich cynics and the poor(er) women who teach them how to feel, that's a tale that was being told before the invention of cinema (Jane Austen made a whole career out of it). One of the reasons it has been so reused is because it's equally suited to comedy and drama.
Have a question? Email us at questions@tvtabloid.com. Please include your name and town. Personal replies will not be provided.