A line or shape sweeps across the screen, erasing the previous scene and revealing the next. The two images themselves don't move. It feels playful and classic.
Retro concepts, chapter breaks, before/after comparisons.
Make it as an editing effect (xfade=transition=wipeleft/wiperight/wipeup). slideleft is a push, where both images slide away together, so it is not the same as a wipe. If you want the feel of a real object wiping across, generate it with "foreground object wipes across frame".
Slide the next clip in with a left wipe lasting 0.6 seconds, joining two 4-second clips of the same size and frame rate: ffmpeg -i a.mp4 -i b.mp4 -filter_complex "xfade=transition=wipeleft:duration=0.6:offset=3.4" -an out.mp4. Swap wipeleft for slideleft or wiperight to change the look.