I like this. Let's do some free thinking about this.
I'd create a Verditius Mystery Virtue called Awakening Items, which would let a practitioner enchant an item with intelligence. Thinking off the top of my head, I'd let the magus compare his Lab Total against a number that includes the item's final Might, its final Intelligence score, and any powers it will have. Ideally, the final product would mirror the Magic Items rules in Realms of Power: Magic.
First season and the magus prepares the item to enchantment. Normal rules. Using a sword as an example, that takes 15 pawns of vis.
Second season. I'd use the Material and Size Tables (ArM5, p. 97) to determine its base Might. A sword would have a base Might of 15. Same Might as its vis cost to prepare for enchantment.
Then, maybe, I'd add Intelligence rules to the formula. Say a base -5 Intelligence adds +5 to the total, and each step up the ladder costs another +5. An Intelligence of 0 adds +30 to the formula. The Verditius needs to double this effect total with his Creo Mentem Lab Total. Giving a sword an Intelligence of 0 is an item effect of 45 and requires a Creo Mentem Lab Total of 90. I like that. It's easier to make dumber Awakened items.
This isn't going to be much fun if the item can't interact with the other characters, so the item needs to be able to talk. Maybe this step is optional for some groups, but ideally I want an awakened item that a player could use as a character. To do that, the item needs to talk. Since I want to encourage talking items, I'd make this part of the process easy. I'd hang it on the item's Intelligence, so that the magus who increased the item's effect level to include a better Intelligence score gets rewarded. I could do this as a separate installed power. Maybe the base Intellego Mentem effect for telepathy is Level 15. +1 Touch and +2 Sun, then +1 two uses per day and +3 environmental trigger (constant effect, page 99) is a level 34 effect, which allows the sword to communicate with anyone hold it. This would cost 4 pawns of vis to install. This is fine, but doesn't address the item's Intelligence score.
Maybe the item's Intelligence subtracts from the cost of installed powers, so that a smarter awakened item actually accepts powers more readily. The speaking feature (above) costs 4 pawns of vis to install in the sword has an Intelligence 0, but only 2 if the item has an Intelligence +2. That's not bad, maybe. Now probably every installed power should have a minimum cost requirement. Effect level divide by 20? Magnitude minus Magic Theory? That's a neat formula, but would it work? I'd try that first.
Additional Seasons and the magus gives the item powers. To follow Magic items rules, I'd like the item to spend Might points to activate powers. So I need a new Frequency Effect to do that. I'd make it cheap to encourage the enchanter to use it. Maybe "use Might pool" adds nothing (0) to the spell-like effect level, just like "1 use per day". Let's give the sword the power to flame up, "Blade of the Virulent Flame" is level 15. That's easy. Normally installing this power costs 2 pawns of vis, using our "minus Intelligence" rules this costs nothing. Well, that's probably not right, so maybe we should say that every power costs at least 1 pawn. So, when the sword activates it's "flame on" power, it spends Might points equal to the level of the effect divided by five, which is fairly standard. Our sword, with a Might of 15, spends 3 points of Might pool to flame on. What if we want to reduce that cost? Well, I'd allow the magus to add to his initial spell-like effect level to reduce the Might cost of the activated power. Maybe adding +10 will reduce the Might cost by 1. So the flame on power with a spell-like effect level of 25 (15 + 10) has a Might cost of 2 (3 - 1). Now that should cost 3 pawns of vis, but if the magus kicked up the item's Intelligence (+2 in our example), it costs less (only 1 for us). I'm starting to like this.
The Awakened Item can hold a number of pawns of vis equal to its Material and Shape number, so the sword can hold 15 pawns of instilled powers. With Intelligence reducing the cost, that is a lot of powers, but there is a cap. Is this too powerful? Probably. So I'd make it a Major Mystery Virtue. It is probably still too powerful, but I'd let players play with those rules and see how they work at the table.
Fun thread, thanks.