Both of 'em are looking nice, I like the alchemist one's tail, reminds me of AJ's mane!

If I were to choose...well, why not both? A mix of an engineer and alchemist? That way she could have both attires, and have more talents~ Plus it's similar, an engineer creates devices and fixes things (ie repairing), an alchemist creates potions and also fixes things (ie antidotes).

But if it's only one, I'd choose the alchemist, I like her appearance more, even though my headcanon is the engineer xP