Rulebook under "push":
Push is an effect caused by some spells and attacks that moves the target into an adjacent zone. Unless the effect says otherwise, the Pushed creature must move one zone away in the opposite direction from the source of the
Push. If there is a choice of direction (such as pushing a creature diagonally opposite, or if the source of the Push is in the same zone as the target), the source of the Push chooses the direction.
1. For a zone attack with a push effect originating in the same zone as the source, can the source select different directions for each target? The RAW appears to allow this.
2. In addition, the Tsunami spell appears to allow the source to select a push direction different than the direction selected for the Tsunami spell when in the originating zone unless I am missing something. Seems an effective way to separate a creature from the rest of a group.
Yes, both are correct... you may choose different directions, as long as both are "away" (farther distant in counting zones) from the source. Also, the choice of direction of the Tsunami spell is completely independant of the choice of any Push effects from the attacks.
Note that this is an effective way to Push a friendly creature to safety while continuing to attack enemy creatures.