No. Just bend your legs more. Watch how people stand in longsword and sabre tornaments. But imo the current animations aren't necessarily immersion breaking during combat.how you imagine that, should he duck in combat? Have you ever been standing in moving bus or train? Spreading legs apart a little bit does improve your stability significantly. If you have to do it all the time on drills and battles you might get used to do it.
The issue op mentioned does become prominent when you're in towns and villages. You shouldn't be standing in combat stance with one leg behind the other when you're not in combat. It's immersions breaking. Combat stance should only trigger when you draw your weapons. I guess the devs' argument is that even with all weapons sheathed your fists are still always 'drawn'.. but I'd argue fists should act like weapon too. Only when you click the mouse buttons should you switch to combat stance. Pressing the sheath weapon button should revert you to relaxed idle standing stance with legs close together and this should be the default animation when you enter a scene.