It's boring. I wasn't nearly as bored by Atomic Blonde as I was by Batman V. Superman, but I still wished it ended far sooner than it did. I don't know if it was just Charlize Theron in this particular role, or her in general, but she had zero charisma in this film. If this film was meant to sell us on the idea that she would make a good, female James Bond, they failed.
All this movie had going for it were some neat visuals, a crazy, bonkers versions of 1989 Berlin, Germany, a softcore, lesbian sex scene, and James McAvoy. Unfortunately, you've seen this character done by McAvoy before in other films. You know what? I wonder if they hired McAvoy to add some much needed charisma to the film, too bad he wasn't enough.
So, unless you want to go watch a porn scene, in public, with Theron and Sofia Boutella, and get away with it by calling it art - skip it.