Please see my last post on this matter, if its info is still relevant under current 1.7.0.
Last time I checked on 1.6.0, the menu limiter would only work if vsync was off ingame. OTH, the non accessible (via UI) ue4 frame-limiter will always be reset and forced at game launch to same fps as current monitor hz when vsync is on. That denies the previous possibility to manually configure it via ini (FrameRateLimit= under GameUserSettings.ini), so a value slightly bellow Freesync/Gsync limit in combination with ingame vsync on to reduce latency can't be set anymore (one must then rely on an external fps limiter).
Both decisions don't seem to make much sense.
