No, but you can create and apply Graphic Styles of the color and transparency you want, to fills, strokes, or both. If the graphic styles are based on global swatches you can change the color of everything at once without affecting the transparency, and you can change the color and/or transparency by opt/alt-dragging a path with the new attributes on top of the previous one in the Graphic Styles panel.
Sorry, I'm not explaining this well — it's late, and I'm getting foggy. Go to the Illustrator Help files and read about Graphic Styles, if you're not familiar with them.
Peter