Hi, I know this is an old thread but I just wanted to expand on this in case anyone else encounters it.
It seems like there is a lot of confusion around the Array Get node, as it sounds in the tooltip like it returns a copy of the Object itself, after some tests, and reading this thread as well as threads Here and Here that what Get is doing is returning a copy of the Pointer to the Object, so when we Get the Object from the Array, then edit the object (ie set its variables), those changes to the Object will also effect the instance of the Object in the Array itself (as they are the same Object, referenced from two different copies of the pointer).
I agree with others on this thread that the wording is highly confusing though. Hopefully I understand this correctly as I am just learning Unreal, so please correct me if I am wrong!