It looks like one big fight. The right hand Green unit is engaged to the front (incidental) as well as the flank. It can, therefore, use half of its attacks to the front as well as the flank.
However, you can split it into two combats. Alright, the right hand green unit is partially in contact with the right hand red unit, but again, the red unit only has partial contact.
The three red units are all in combat with the left hand green unit (all of their centre points are in contact with the one green unit). So, the question is “whose turn is it?”. You see, whoever’s turn it is chooses which combat to start with. If Red’s then Start with the left hand combat – more chance of winning and possibly sweep into the right hand unit.
If Green’s turn, there is a risk, but would probably start with the right hand combat. The risk is that if Green loses, it could be destroyed if it has to fall back into the other green unit. If it wins, it could then follow up should the red unit fall back.
I think I’d seperate them for ease.
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