Is it possible and if so how, to clone an actor into multiple actors against a static background in Kdenlive like one sees in some of the youtube home-recorded music videos ?
There's a tutorial using Premier Pro that explains the concept: https://www.youtube.com/watch?v=B3AqxXYBm28

For a situation like the one in your example video, you can use a "Rectangular Alpha mask" effect on the top clip and then add something like an affine or a composite transition between both clips.

If your scene is more complicated you will have to rotoscope it (see: https://www.youtube.com/watch?v=rPQWOGDng-Q) and then add the transition.

https://www.videomaker.com/courses/1727 ... one-effect There is link for how to a clone effect

And here is how it is done in Kdenkive -https://youtu.be/vxaBKi5v678