This is an interesting topic but one that feels very straightforward for Issac. If he were to be placed into the world of Avatar, and lucky enough to bend a natural element, it would have to be the earth. He works with his hands and is grounded in the most resolute way, both in mind and in the body. Not to mention his affinity to work with metal of all types. He would be an Earth bender, leaning heavily into the metal bending aspect of the style.