Is there a way to control the transparency of multiple objects using a single style?

I have many objects, and they all use the same transparency settings.
I’ve found that the “Appearance” and “Transparency” styles can only be applied to an entire layer and don’t allow for flexible control over objects on different layers.

I have to select the object every single time just to adjust the opacity—that doesn't make any sense…

I tried using “Graphic Styles,” but found that they can’t be modified later.

In InDesign, there are object styles—is there a similar feature in Illustrator?