4Game

I BELIEVE I HAVE A SOLUTION!!
Swap around the attack order and layout!!.

Change the first swing in the combo into the current M3 stab/jab

. This makes the weapon more reliable against single targets, I would add a reduction in stagger on the jab, but keep the heavy stagger on the horizontal sweeps,
(I would also recommend making the continuous (held m1) attack for all battleaxes only do sweeps.)

Lastly,
The number 3 Overhead swing in the current battleaxes combo can be the new power move bound to M3, in place of the stab/jab. This jumped out at me as the main change that needs to happen. As of currently, you need to commit to a 3-swing-combo, which ends in the Chop.

If we translate the stamina cost for chopping as equal to three M1 swings; changing M3 to chop with a large Stam cost would do two things.
Give players a very slow, high risk special attack with high stagger,
As well as push the jab into the main combo, which would have the chop "cut" from it.

These changes would make both axes feel IMMENSELY more fluid to use in combat, while still being slow, strategic weapons.
Being able to initiate with an M1 jab, and holding M1 to swing side to side could help players act more aggressively, and target-switch on the frontlines. And chopping is like music to the ears Vikings. Let is split our foes in twain!