The only way I’ve found is sort of convoluted, but faster than applying attributes to every single instance–
For the clip you want to change, take the original, place it in a new sequence, and make the changes to it that you need. Then export the sequence, making sure that it is the same length as the original, with the same name as the original file. Place this new file in the folder where the original lies, move the original (don’t delete it yet, until your sure this process has worked). Now the clip in FCP will reconnect with the new file, and voila!
This has worked wonders for me with out of sync sound. Not sure how it’ll work with the color correct, but I imagine it’ll be pretty much the same.