demo, MySQL - rextester

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#MySQL 5.7.12
#please drop objects you've created at the end of the script 
#or check for their existance before creating
#'\\' is a delimiter

DROP TABLE IF EXISTS yourTable;
CREATE TABLE yourTable (id int, res1 varchar(55), res2 varchar(55));
INSERT INTO yourTable (id, res1, res2)
VALUES
    (1, 'a', 'f'),
    (1, 'b', 'f'),
    (1, 'b', 'f'),
    (1, 'c', 'f'),
    (2, 'e', 'g'),
    (2, 'e', 'g'),
    (2, 'e', 'g'),
    (2, 'f', 'g');

SELECT
    t1.id, t1.r1, t2.r2
FROM
(
    SELECT t.id, GROUP_CONCAT(res1agg ORDER BY res1) AS r1
    FROM
    (
        SELECT
            id,
            res1,
            CASE WHEN COUNT(*) = 1 THEN res1
                 ELSE CONCAT(CAST(COUNT(*) AS CHAR(50)), res1) END AS res1agg
        FROM yourTable
        GROUP BY id, res1
    ) t
    GROUP BY t.id
) t1
INNER JOIN
(
    SELECT t.id, GROUP_CONCAT(res2agg ORDER BY res2) AS r2
    FROM
    (
        SELECT
            id,
            res2,
            CASE WHEN COUNT(*) = 1 THEN res2
                 ELSE CONCAT(CAST(COUNT(*) AS CHAR(50)), res1) END AS res2agg
        FROM yourTable
        GROUP BY id, res2
    ) t
    GROUP BY t.id
) t2
    ON t1.id = t2.id;


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