1st battle is sacrificing 6 merc to kill Queen bees. 2nd battle, it is important to follow the same attack order, so that Christina will trigger set effect to attack the turtle. Also note, put the robot in front to counter Shock.
☆☆☆ Chapter Ⅲ Outerskirts 1-2 ☆☆☆
Alternative is Jin only on mid row.
☆☆☆ Chapter Ⅲ Outerskirts 1-3 ☆☆☆
Alternative is Jin only on bottom row.
☆☆☆ Chapter Ⅲ Outerskirts 1-4 ☆☆☆
☆☆☆ Chapter Ⅲ Outerskirts 2-1 ☆☆☆
1st battle is to kill 2 and 7, then finish it on 2nd battle. Don't forget to take care of Shock counter on 2nd battle. BTW if you have Beliath, I think you can clear this stage at once.