Two databases same server with different time zones
If you just want to store the same data and have it automatically converted to the timezone of the client, that is just a matter of a session level setting with TIMESTAMP WITH LOCAL TIME ZONE Datatype. Example:

SQL&gt; create table t1(c1 timestamp with local time zone);

Table created.

SQL&gt; alter session set time_zone = '+02:00';

Session altered.

SQL&gt; select current_timestamp from dual;

CURRENT_TIMESTAMP
---------------------------------------------------------------------------
03-JUN-19 07.05.01.908465 PM +02:00

SQL&gt; insert into t1 values(current_timestamp);

1 row created.

SQL&gt; commit;

Commit complete.

SQL&gt; alter session set time_zone = '-09:00';

Session altered.

SQL&gt; select * from t1;

C1
---------------------------------------------------------------------------
03-JUN-19 08.05.11.187305 AM

SQL&gt; insert into t1 values(current_timestamp);

1 row created.

SQL&gt; commit;

Commit complete.

SQL&gt; alter session set time_zone = '+02:00';

Session altered.

SQL&gt; select * from t1;

C1
---------------------------------------------------------------------------
03-JUN-19 07.05.11.187305 PM
03-JUN-19 07.05.36.714308 PM

SQL&gt;


If you really want to store both the timestamp and the timezone offset, then you can use TIMESTAMP WITH TIME ZONE Datatype.