Using the ‘Dissolve Blend’ To Create Dispersion
It is easy to forget about the less used Blend Modes. Try this quick dispersion effect if you have a subject that is easy to extract from the background! The first Screenshot shows the effect; the 2nd the original image.
Extract the subject and make an extra copy of the extracted Layer. Run a Motion Blur on the lower layer (Screenshot 3).
Set the layer to a Dissolve Blend Mode (Screenshot 4).
Try resizing and moving this ‘dispersed layer’ and adding Layer Masks to refine the effect.