Hello Joker! when you say "Export only whole frames" do you mean as png/video exports?
You can set the framerate of the export in the settings for gifs, pngs, and videos. Therefore if you match the framerate of the editor with this kind of export you shouldn't encounter problems.
If you want to export for a runtime, knowing which runtime you're targeting would be useful, but setting the framerate for the animation should be possible as well.
I'd be interested in understanding what kind of jitter you're encountering and if this may be solved directly in the editor though, is this a problem with legs for example?