1. Dual wield.

2. Use one-handed swords.

3. Use a staff as a main-hand only, one-handed weapon.

It also increases the Lore-master's maximum morale, parry and evade, and melee damage.

Important note:

A staff can only be equipped in the main-hand. However because this trait gives you the ability to dual wield and use one-handed swords, you can actually equip a sword in both hands. Unfortunately, most Lore-master skills require a staff in the main-hand. This includes the Lore-master's one melee attack skill, Staff-strike (or the traited improved version of that skill). Thus while a Lore-master with Sword and Staff slotted can dual wield two swords, all they will be able to do is auto-attack and cast a couple of non-combat skills (e.g., Leechcraft) that do not require a staff be equipped.

Thus, the only viable option is to equip a Staff in the main-hand and a One-handed sword in the off-hand.