As i understand to your question on where you do able to know on whats ethereum wallet which had been used by other people who sent coins to you then its not possible because there are lots of
address which neither belong to an exchange or solely their own eth wallet address.You can somehow observed if it came from an exchange basing of transactions and the coins been holding
but identifying specifically on what exchange then i dont think that it can really be identified literally but if you do make up some search to trace it up then you would know it for sure.
but talking about identity on someones wallet then its impossible to happen.