There is ideas, how to rotate a lot of objects around their each center?
- Select one object and convert it to a Symbol
- Repeat with all the objects
- Select one of the repeated symbols and the original symbol thumbnail at the Symbol Panel
From the Symbol Panel options menu choose Replace Symbol
Do the same with the others
If everything is right, when choosing Select Unused from the Symbol Panel options menu the only one unselected will be the original symbol
Edit the original symbol clicking twice and rotate it