We have a requirement where in we need to search for duplicate contacts ( based on contact email , first name, last name etc). Once all duplicates are listed to the user , then they can choose the valid one. We were hoping to use flow using Record lookup functionality. Is there a way we can do a record lookup and list the resultset in a screen element.
Unfortunately the Record Lookup element only returns one record, see the implementation guide here. See the Record Lookup section, which says 'The Record Lookup element ultimately returns only the first record from the filtered results'.
You might be able to achieve what you want with a Flow ApexPlugin making the query and providing a list back to the Choice display element. Though I suspect your wanting to be code free here.
I am not sure if you are or have searched but there is quite a few duplication checkers / removal tools for Salesforce. Try searching AppExchange.