So you want to search for copies that could exist in other projects as well? Are you using imported baselines between projects or just doing manual copies of entities?
If you are referring to manual copies of tests and requirements, how would you decide whether two items are equal? The description field and name being identical? I think it would be very expensive in terms of performance to tracks such copies, and when you found a copy, how would you decide whether it is a unsolicited copy or not?