I agree with method mentioned by @stanner.austin since AFAIK there's no wallet which such specific feature. Getting rid of unused private key isn't good practice either.
Match with known funded address (both compressed & uncompressed) if match save his output WIF .
This won't need internet i am unsure about process speed i tested myself 1000 line take less then 1min.
But if there's no list of known funded address, you either need to use blockexplorer API or list of all funded address (such as
addresses.loyce.club).