For instance, if I select 4 objects on the page, and under the transform docker, choose to rotate 90 degrees, it rotates the entire selection 90 degrees. Is there any way to have it rotate each object 90 degrees (about its own individual axis?)
If there are only 4 objects, it is not necessary to install a macro for that. Rotate one of the objects, select another (Tab select objects sequentially) and press Ctrl + R (to repeat the last action)