There's another kind of Lost Ark Gold engraving. There are a few disadvantages, and might reduce your attack speed as well as damage, defense or speed of movement. I'll be back on these jerks later on.
When you've completed the West Luterra portion from Lost Ark, two slots on your character profile's gear tab open under the slot to hold weapons. Each slot has an engravings embedded inside them. There are equippable class engravings and fight (or "combat") engravings within their submenu that you bring up by pressing alt-I. You'll initially not be able to equip anything, because you need to learn how to make them through reading recipes.
The relevant tutorial quest will give you some as well as a plethora of the green satchels that contain engraving recipes as rewards to complete the sidequests East Luterra, and a couple more within Tortoyk, Annika, and Arthetine. Engraving Recipe Pouches offer random recipes, while engraving Recipe Selection Pouches allow you to choose which recipes they're stocked with and should be saved for when you've decided on the type of build you'll be using. There are separate pouches specifically for combat and class recipes, as well. (Sometimes the latter are called 'combat' recipes, however, they're exactly the same as battle recipes.)
Right-click the books you get from pouches Lost ark gold buy to find out the recipes inside. If you have a pile of them, alt-clicking will let you use more than one at a time as is the case with any other set of consumables.