All weapons are separated by tiers and for most of them there are 3. Example is:
Each tier is a straight upgrade of a lower one and there’s no reason to use lower tier weapons when you get your hands on a better one. I’ll post my opinion about the weapons I used frequently here:
Let’s start with daggers: it’s a very niche weapon. It’s primary use is to spam skill that ignores enemy armor completely but has a -15% hit chance. A very high melee skill is required to use it effectively but when used correctly you can easily kill even the strongest opponents. I use daggers in midgame to obtain some high level armor and helmets from bandit leaders and I must say I really love this weapon.
Swords: Great against elusive opponents since basic slash gives you +10% hit chance and with mastery you can make a viable riposte build. But I believe for each hit you dodge you gain some fatigue now so I’m not sure if you should dedicate that much into swordsmen. Overall, good weapon for your low melee skill guys, great against unarmored opponents.
Spears: Just as swords, a very useful tool against opponents with high melee defense. But spears also allow you to use a special skill called “spearwall”. If opponent tries to enter your zone of control with spearwall on, he triggers a free attack. On a hit, your opponent is pushed back to the tile he tried to advance to you from. Against zombies and ghouls and in some cases direwolwes this weapon can be amazing and there are even dedicated spear builds. Personally I don’t use them that often (maybe because I fight with orcs too much) but they’re great.
Axes: During the course of campaigns I played I found myself sticking to this weapon from early game all the way up until late game. This weapon is your jack-of-all-trades: it has reasonable damage, it is decent against armor, it can destroy shields if necessary. But for that versatility you pay with fatigue, especially on high-tier variants.
Hammers: This is your primary tool to deal with armored opponents because of the special attack that is devastating against armor. Even low-tier variants are good and late game you should dedicate some guys to use this weapon as a primary against all these orc warriors and knights.
Maces: This weapon is great for fatiguing your opponents and it is your weapon of choice if you want to use stun ability. Since you can even stun the undead, it’s a fun weapon to use.
Flails: Not only there’s an extra chance to hit the head but you also get the special attack that only targets the head (which is fatiguing though). An interesting weapon for sure and is reliable on all stages of the game. Mastery perk makes it ignore the bonus of shields which makes this weapon amazing. And, of course, there’s the berserk chain – one of the most interesting 2-handed weapons to use.
Cleavers: Not only you get the highest damage potential with cleavers (especially with orc ones) but there’s also an additional bleeding damage applied over turns. Plus you get a special decapitation attack which is great against zombies. This is one of my favorite weapons.
Greatswords: Right now they dominate in the game, mainly because you get three types of attacks: a normal single-target, an attack that targets the target next to you and the target behind your enemy and a sweeping attack that can hit up to 3 opponents. Some people even make entire companies armed with this weapon.
Greataxes: If you compare a Man Splitter (orc greataxe and that is the weapon you should aim for if you go for those) to a Greatsword, you get better damage and better effectiveness against armor. But its rounds swing is difficult to use and is unreliable. And as I mentioned before, long axes are one of the best (if not the best) 2-tile weapons.
2h Hammers: Haven’t tried them yet but I once fought against an opponent who had a hedge knight in his group armed with this weapon. It has some amazing damage potential and is devastating to armor. A solid choice if you wish to go for it.
Polearms: Here it’s mainly a rivalry between a pike and a billhook. Even though pike has less damage it’s secondary ability – repel – is much better.
Ranged weapons: Bows are great against unarmored targets and are great to spam arrows, crossbows are for armored opponents. I think you should get at least two archers in your group and use one with bow and one with crossbow, since the latter gets less range but is easier to use. Top-tier weapons allow you to deal with any threat (and special goblin crossbow called spiked impaler can push your enemies back on a hit).