Kimberly naturally hoped to borrow the Alchemy Weapon that eliminates the undead; however, exchanging Alchemy Technique was also one of her purposes.
The alchemy heritage Kimberly had received was actually a thousand-year-old Alchemy Technique. Not everything older is better, techniques like Alchemy are certainly more representative of the current generation the more cutting-edge they are.
In Kimberly's mind, Angel was a talented Alchemist, but perhaps due to his age, his Alchemy Technique might not be that strong. However, from his previous work on repairing Natasha's mechanical half, it was evident he must have encountered cutting-edge Mechanical Alchemy. Such an exchange would also allow her to quickly grasp some of the current situations in Mechanical Alchemy.
