Short answer: nope.
Plugins make their own folder/bin.
What version of Premiere?
I have tried to figure a way to sort my BCC plugins in Ae (CS6)
without success (BCC in Ae CS5 is organized by type of effect).
In Ae, they are all lumped together into a folder named 'Other'.
At least in Premiere CS6, they stay categorized by type of effect
(even if transitions are in the Effects folder).
CS6 Suite on Window 7.
At least it does say BCC Transitions & FEC Transitions even though they are in the Effects Bin. I was hoping to move them so I don't forget about them.
I've discovered how to create other bins but not how to put third party plug-ins in it.