Yes... sort of...
In your example, as each hex is entered one of the enemy groups could fire on the moving stack. But only once each.
For example, you have moving friendly unit(s) in A1 and they want to move to A2 then A3 then A4 then A5. All of the hexes are in LoS of enemy units B(ad)G(uy)1, BG2, BG3 and BG4. Each of the BGs is in a different hex.
So you unit(s) move from A1 to A2, using 1 MP. BG1 fires at them, and misses. BG1 gets marked Fired and can do no more until next TURN.
Good guys move from A2 to A3, using 1 MP. BG2 fires and also misses. BG2 gets marked Fired.
And so on if each hex entered that costs 1 MP.
But lets say the Good Guys move from A3 to A4 and it costs 2 MP. Then BG3 could fire and see what result they get and get marked Fired and then BG4 could also fire at A4 to add insult to injury and then get marked Fired.
Hope that helps.