Try turning off Export > Video > Parallel processing. If that works, then some filter or combination of filters is not handling the frame-threading correctly. You can provide the project file to help.
I’ve already replaced that part, and now it’s fine.
But[TM] , as you can see there are two parts on the track near 00:02:19:08, where that “line” (do not know the correct name) is posed (third pic). As I’ve removed the part in front of that transition, and then the transition, the following part, that image, was “lifted” (ca. 100, 150 px) (and that was to see in the editor<!>, I also replaced it). But on both parts, I hadn’t any keyframe, only simply filters. But , and IIRC, I previously had keyframes on one, or both.
So I may say, that the glitch, previously in the first part, moved to the second one (or so )…, is’s hard to explain. But I hope I could explain it understandably…
(Before sending I looked again correction…, all fine )
--------------- EDIT ---------------------
Providing the project file: Hm, over 200 MB… But, thanks.