Using IS Boxer...

A two-step mapped key.
Hold keystrokes, while hotkey is held.

Step one.
Sends Q to two toons.
Sends E to two toons.

Step two.
Send Q to one of the initial two toons.
Send E to one of the latter two toons.

Middle toon does not move.

If you don't have the equivalent of "steps", where different presses of the same key result in different actions.
Then go with two hotkeys, one sending the keybind to several toons.
And one to fewer toons.
Or set a primary and secondary keybind for strafe.
But set them differently across your toons, so you can move some but not others.