On trace hit, you can get the index that that instance is stored in in the TArray which the engine creates in the background to store it.
This isn’t super handy if you’ve got multiple different types of meshes instanced though, because info about WHICH TArray that index is in is not exposed.
However…I was able to get around this by storing the world position of my instances, along with info about ‘what’ they are in a separate struct array. Then I compare the word position of the instance to the array to find a match and retrieve the info that way.
Obv that is not going to be super scalable if you are looking through thousands of records, but it works.