Hello,
Using the search functions, eventually looking for "oceana controls", you will find some indications that should answer your question about MSOceana (http://80.95.161.114/shipsim/forum/index.php/topic,28720.0.html) handling. They will indeed confirm ave160's post validity.
Sorry about the "old school" description. One engine ahead, one astern would of course produce zero side thrust, the propwalk of one thruster would even cancel the propwalk of the other thruster.
The side thrust at the stern is gained by the rudder lateral thrust when set at an angle, propeller ahead. The forward thrust can then be cancelled by the other propeller, and the torque on the ship resulting from the thrusts of the propellers must be overcome by the bow thruster. It was indeed designed to be easier in SS 2008 than in SS Extremes.
Moving MSOceana sideways could as well be done by setting one thruster ahead aiming at the centre of lateral resistance, the other aiming away from the centre, in order to help the bow thruster if the latter is not enough powerful.
Regards,
Luc