MYSQL Select data from two different tables BUT represent the data in multiple rows
SELECT id, First_Name, Last_Name, 'Email' Name, Email Value
    FROM table1
UNION ALL /* or UNION DISTINCT */
    SELECT tb1.id, tb1.First_Name, tb1.Last_Name, tb2.Name, tb2.Value, 
    FROM  table1 tb1
    LEFT JOIN table2 tb2 
        ON tb2.Name LIKE '%email%' 
       AND tb2.Value LIKE '%@%' 
       AND tb2.client_id = tb1.id  
/* ORDER BY 1 */


PS. AND tb2.value != '' condition is excess. If false, then AND tb2.Value LIKE '%@%' is false too.