It sounds like you might be interested in writing an editor script.
You could write a function that gets invoked by a menu item that could do what you want.
One easy way to do it would be to use the Selection object, which allows you to select an object in the project or hierarchy and perform operations on it.
If you’re talking about changing settings when assets are imported, you might want to look at the AssetPostprocessor class, which lets you specify various functions to get executed whenever various types of assets get imported: