There have been several users that have spoken of this stutter on Ryzen chipsets. I don't think there is any definitive workaround. I have the same type of stutter on my i7-4790K, but I do NOT see the stutter on the i5 or i3 systems I've worked with. So, my belief is that it has something to do with multithreading and chipsets with more than 2 cores.
What I did to completely rectify it on my system is lock FPS to 48. You can edit you user.settings file, and change LimitFPS=48. Also try values of 50, 52, 54, and 58. Normally, one of these will be a "sweet spot" that clears up frame-timing issues in various games. (I've solved almost all such problems I've hit in the past by doing this.)
You'll also want to try each setting with Vsync on/off and Fullscreen vs. Windowed. Forcing settings through Nvidia Control Panel or programs like Nvidia Inspector or RTSS may also yield different results, instead of using the in-game settings.
In short, it's a system-by-system quirk. The good thing is that once you find a combo that works on your system, similar settings will often work for other games.