I learned to string walk out of curiosity, but don't use it much because it is not allowed in the tournaments I shoot in. I also learned the fixed crawl, which is an offshoot of string walking, I guess, and use that method in hunting (theoretically, although I haven't been successful in actually killing anything while using it yet). Both methods improve my accuracy over gap shooting.
The point of both methods, the way I understand it, is to allow you to put the point of the arrow on the spot you want to hit, rather than above or below the spot you want to hit. I don't really understand how that would help you with your cross dominance problem, other than the way they help anyone improve accuracy in general. What did you have in mind?
By the way, I also learned to shoot both right and left handed, and really enjoy doing that. I don't consider myself particularly gifted, and I would say that within a month I was shooting left handed without feeling awkward about it. Within six months I was shooting left handed probably as good as I’ll ever get at it, considering that’s cross dominance for me, but good enough to be enjoyable when I decide to switch hit.