Key Selected Objects adds much-needed multiple-object keyframing options to Blender’s context-menu. If the target property is multi-dimensional (i.e. a property with X, Y, & Z values), you’ll get the options to create & delete keyframes on a single dimension for all selected objects. If it’s a single dimensional property (e.g. a Light Object’s “Power”), you’ll just see “Keyframe All Selected Objects” and “Delete Keyframes for All Selected Objects”.
Note
If your selected object doesn’t have the mode specified in your Keyboard Shortcut (e.g. if you create a shortcut for the Grease Pencil Draw Tool and use the command on a Metaball object), you will see an Error Message.