I agree that the wrist-twisting strikes with the 1-handed and 1.5-handed swords would require a different control system. So forget that. However, seems to me you can use the same game commands to trigger different sets of attack animations appropriate to the weapon being used. Maybe add just 1 command to switch grips (which would then use a different set of attack animations) if that's possible for the weapon and if the character has learned the technique.
Thus, if you have a short polearm (bill, warhammer, spear, or expedient things like cage bars), the default animations would have you holding the thing centrally. RtL attack would be with the butt, LtR would be with the head, and it would use the stab with the double-click instead of the overhead. And that's it. No different command-wise from what we have now except the weapon now moves as it should and is useful in confined spaces.
With a 2-handed sword or battleaxe, its default would be as now. But if you learn the technique, you can tap a key to switch grip, in which case it works like a short polearm as above.
With a 1-handed sword, its default is as now but it would be switched to half-sword if you know that technique and don't have a shield. When in half-sword mode, its animations would be like a normal 2-handed sword except you're holding it by the blade and it does impact and mayby piece damage instead of slashing.
Other 1-handed weapons (mace, tomahawk, etc.) and long polearms (glaive, etc.) remain as now with no optional modes.
Anyway, seems to me something like this would be a nice addition to the game without requiring major changes to the overall command system.
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