Find instances with an effect - Search by effect name

Hi all,

I want to find instances which has the effect blur with the name Blur2.
Reason is all instances with the name Blur2 has to change to Blur3.
(The values are different in Blur2 and Blur3)

Is there a plugin or what is the best way?

I know I can change the value of Blur2 to match Blur3 but I dont want to have two style definitions with the same value.

Thanks