I feel hard to understand the tables structure and your required
result, mainly my poor English capabilities.
Especially, this part is difficult for me.

It is difficult to explain by English my understandings.. So, I'll show
you by Example. It may include my misunderstandings, please don't
hesitate point out them..

By the way, I have some questions
1) How to math value of T4 with another tables data.
2) Are there any meaning in that the value of T3 are descending.

If you give us an example including more various cases. It will help
greatly us to understand the problem.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T1;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         1 A
         1 B
         2 A
         3 A
         3 B
         3 C

 6 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T2;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         3 a
         3 b

 2 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T3;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         1 Z
         1 1
         3 Z
         3 Y
         3 X

 5 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T41;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         1 G

 1 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T42;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         1 I

 1 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T43;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         1 K

 1 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT * FROM P175.T44;
-------------------------------------------------------------------

ID          VALUE
----------- -----
         1 H

 1 record(s) selected.

------------------------ Commands Entered -------------------------
SELECT
      COALESCE(t1.ID, t2.ID, t3.ID, t4.ID) AS ID
    , t1.value                             AS T1
    , t2.value                             AS T2
    , t3.value                             AS T3
    , value41||value42||value43||value44   AS T4
 FROM (SELECT ID, Value
            , ROWNUMBER() OVER(PARTITION BY ID
                                   ORDER BY value) rn
         FROM P175.T1
      ) AS t1
      FULL OUTER JOIN
      (SELECT ID, Value
            , ROWNUMBER() OVER(PARTITION BY ID
                                   ORDER BY value) rn
         FROM P175.T2
      ) AS t2
        ON  t2.ID = t1.ID
        AND t2.rn = t1.rn
      FULL OUTER JOIN
      (SELECT ID, Value
            , ROWNUMBER() OVER(PARTITION BY ID
                                   ORDER BY value DESC) rn
         FROM P175.T3
      ) AS t3
        ON  t3.ID = COALESCE(t1.ID, t2.ID)
        AND t3.rn = COALESCE(t1.rn, t2.rn)
      FULL OUTER JOIN
      (SELECT COALESCE(t41.ID, t42.ID, t43.ID, t44.ID)
            , COALESCE(t41.value, ' ')
            , COALESCE(t42.value, ' ')
            , COALESCE(t43.value, ' ')
            , COALESCE(t44.value, ' ')
            , ROWNUMBER() OVER(ORDER BY
                                     COALESCE(t41.value, ' ')
                                   ||COALESCE(t42.value, ' ')
                                   ||COALESCE(t44.value, ' ')
                                   ||COALESCE(t43.value, ' ')
                               DESC
                              )
         FROM (SELECT ID, Value
                    , 1 rn
                 FROM P175.T41
              ) t41
              FULL OUTER JOIN
              (SELECT ID, Value
                    , 2 rn
                 FROM P175.T42
              ) t42
                ON  t42.ID = t41.ID
                AND t42.rn = t41.rn
              FULL OUTER JOIN
              (SELECT ID, Value
                    , 3 rn
                 FROM P175.T43
              ) t43
                ON  t43.ID = COALESCE(t41.ID, t42.ID)
                AND t43.rn = COALESCE(t41.rn, t42.rn)
              FULL OUTER JOIN
              (SELECT ID, Value
                    , 4 rn
                 FROM P175.T44
              ) t44
                ON  t44.ID = COALESCE(t41.ID, t42.ID, t43.ID)
                AND t44.rn = COALESCE(t41.rn, t42.rn, t43.rn)

      ) AS t4 (ID, value41, value42, value43, value44, rn)
        ON  t4.ID = COALESCE(t1.ID, t2.ID, t3.ID)
        AND t4.rn = COALESCE(t1.rn, t2.rn, t3.rn)
ORDER BY
      ID, COALESCE(t1.rn, t2.rn, t3.rn, t4.rn)
;
-------------------------------------------------------------------

ID          T1 T2 T3 T4
----------- -- -- -- ----
         1 A  -  Z  G
         1 B  -  1   I
         1 -  -  -     H
         1 -  -  -    K
         2 A  -  -  -
         3 A  a  Z  -
         3 B  b  Y  -
         3 C  -  X  -  

 8 record(s) selected.