Below query can be used to for PDB creation/cloning time.

COLUMN DB_NAME FORMAT A10
COLUMN CON_ID FORMAT 999
COLUMN PDB_NAME FORMAT A15
COLUMN OPERATION FORMAT A16
COLUMN OP_TIMESTAMP FORMAT A10
COLUMN CLONED_FROM_PDB_NAME FORMAT A15
 
SELECT DB_NAME, CON_ID, PDB_NAME, OPERATION, OP_TIMESTAMP, CLONED_FROM_PDB_NAME
  FROM CDB_PDB_HISTORY
  WHERE CON_ID > 2
  ORDER BY CON_ID;

Here is a sample output of the query:

DB_NAME    CON_ID PDB_NAME        OPERATION        OP_TIMESTA CLONED_FROM_PDB
---------- ------ --------------- ---------------- ---------- ---------------
NEWCDB     3      HRPDB           CREATE           10-APR-12  PDB$SEED
NEWCDB     4      SALESPDB        CREATE           17-APR-12  PDB$SEED
NEWCDB     5      TESTPDB         CLONE            30-APR-12  SALESPDB

For specific PDB

You can find the creation or cloning time for a specific pluggable database by using the below query:

SELECT DB_NAME, CON_ID, PDB_NAME, OPERATION, OP_TIMESTAMP, CLONED_FROM_PDB_NAME
  FROM CDB_PDB_HISTORY
  WHERE CON_ID = [conainer ID];

Replace the container ID in the above query with the container ID for which you want the creation time.