Yep I said something similar, but I'd base it on weapon type:
2H Long Pole Arms - 2 tiles range - Bardiche, Halberd, Spear, Pike, Bladed Staff, Pitchfork
2H Axes - Extra lumberjacking damage while on foot - Axe, Executioners Axe, Battle Axe, Double Axe, Hatchet, Ornate Axe, Two Handed Axe, Large Battle Axe
2H Staff - Extra parry chance - Black Staff, Gnarled Staff, Quarterstaff, Crook, Gargoyle staves
2H Mace - Ignore stamina loss reduction from heavy armor - War Hammer, Nunchaku, Tetsubo
2H Sword - Hits multiple targets in front arc - Daisho, Scythe, Crescent Blade, No-Dachi, Runeblade, Talwar,
2H Offensive Fencing - Ignores 5 points of resist on target? - Spellblade, Double Bladed Staff, Sai, Short Spear
2H Defensive Fencing - Increases DCI (less than parry effect, but is not skill related) - Tessen, Kama, Tekagi, Layatang