If they all need the same Effect, just apply it to the first Clip/Still Image, and adjust, as required. Then, Rt-click on that Clip/Still, choosing Copy. Now, Select all others, Rt-click on them, choosing Paste Attributes. Done.
PS - if needed, though you did Paste the Attributes, you could still manually tweak each one, as needed.
FYI, in version 11, Paste Attributes is called Paste Effects and Adjustments.
Thank you for that correction. Maybe one day I will get all of the syntax changes straight in my mind - and then they will be changed again.
After about 8 years, PrPro made some changes in verbage too, to make FCP, and AVID switchers feel more comfortable. Just more to learn.