Engineering is a stalwart profession for raiders for the PvE benefits. On the goldmaking side it has had it’s up and downs between expansions, so let’s look at the MoP view.
No longer engineer-specific
One big change in Mists of Pandaria is that almost every PvE usable item you can craft no longer requires engineering to use. This is true for both the bombs you can craft and the dragonling trinket. This means you have a much bigger market than in previous expansions.
Mist-piercing goggles
This is a new type of goggles that adds more herbs/ores to the world if you wear them. Pretty much every farmer will want these, and the recipes is trainer learned, so it can be a nice goldmaker.
Consumables
The main consumable you can craft and sell is the G91 Landshark, the new bomb. It does also come as a reward from Blingtron dailies however, so the price can end up being lower than the crafting cost. If it isn’t then this one can have a real market as it’s not restricted to engineers.
Gear
There are three relevant gear recipes. You can craft two different guns for hunters that may be useful for pre-bis gearing and gearing while leveling. Lastly the Ghost Iron Dragonling trinket is equippable from level 87 and is VERY strong. With 3 Cogwheel sockets you can fill for massive stat boosts this was a massive seller back in the day. The Tinker’s Gear cogwheels was also something I made a good bit of gold selling in original Mists, so this whole supply chain is very likely to be good again.
Scopes are back
There are two new scopes in Mists Lord Blastington’s Scope of Doom is the more expensive variant and will be the best one. The recipe is learned from your trainer, so competition will likely be pretty high.
Mounts
With 5.0 we will get two new mounts, one for Goblin Engineers and one for Gnomish engineers. The two rockets are very expensive, requiring thre Orbs of Mystery which cost 20 000 gold each from the rare materials vendor. They also require 12 Spirits of Harmony. I would only craft one if you have a buyer lined up that you can trade materials and gold for a finished mount, unless you like to gamble. Later in 5.4 the best goldmaking mount in a while is getting added. The Sky Golem allows you to herb while mounted, and it is incredible for that reason. It requires 30 Jard’s peculiar energy source which is a BoP daily cooldown to craft, so getting alts ready can be profitable to get more mounts per 30 days.
Blingtron
Blingtron 4000 is the new version of Blingtron. It is BoP, but making sure you grab your daily gift can be very valuable. The gift can even include the expensive Orbs of Mystery, so make sure you get the gift. Blingtron is a little expensive to craft, but over the course of the expansion it will be worth it.