If your shrubs are deciduous, you can wait for the leaves to fall off and then dispose of the leaves.  If your shrubs are evergreen, sometimes the sooty mold will harden and flake off over time.  Be sure to dispose of any leaves that fall since insects and disease can overwinter in plant debris.  Watch for aphids next spring and treat them as soon as you see them.

You can also use a soap and water mixture to spray on the leaves and then wash it off.  Here is some information on sooty mold and using soap and water to wash it off.

The Plant Doctor - Sooty Mold | Mississippi State University Extension Service (msstate.edu)

Thank you for contacting Ask Extension.  If you have additional questions, please contact us.