Had to move a clip partially out of frame, how to deal with the new empty space?
It is possible to take a similar approach like you would in photoshop. I recommend using After-Effects, as premiere doesn't really have the abilities to do so effectively. In After-Effects, you can try out the &quot;content aware fill&quot; that was introduced in 2020, I believe.
However, content awareness only works in some cases, and when trying to seamlessly continue the motion and behaviour of cloth, this could get tricky. So let me propose two more options, one simple and one that requires some more work.
First off, you could just use a gradient from blue to alpha, and let the solid blue fade out over the shirt, with the solid's area of 100% opacity just touching the right side of your clip, in order to conceal the edge.
The other method is tricky, and I frankly never tried this myself. You could actually go out of your way and try to simulate cloth using a projected texture from your footage in a 3D-software such as Houdini, Cinema4D, Modo, Blender or something similar with the ability to simulate cloth. In order to match the motion, you could try a cloud-tracker, such as Mocha or the integrated tracker from Resolve and try to apply the vertices of the left side of your simulation to the most right vertices of your cloud-tracking-points. This could work, but I am not 100% confident that it will.
Anyways, I hope this helped you out a bit, have a good one :)