I'd sous-vide. I haven't done Japanese Kobe, so maybe someone else can weigh in on temperature. My first thought is to set the circulator to 55°C, aiming for an internal temperature of 54°C. It's important to cook it far enough into medium-rare territory that you melt the marbling, otherwise you'll get a waxy, greasy mouthfeel. Cook only until cooked through. Any longer will just lose juices and mess with the texture. Cutting the steaks to 1.5" thick is ideal in terms of time and ease of browning.
Finish on the stove. Go for browned, not charred and crispy. You don't want to mess with the delicate flavors. I'd salt the sv'd meat, let it sit while the griddle or pan preheats, and at the last minute dust with baking soda / glucose (I use a 1:5 ratio). This will speed maillard reactions so you can get solid browning without introducing burned fat flavors, or overcooking below the surface.
The steaks can be served whole or sliced for service (won't matter which direction you slice).
Sauce is up to you, of course, but whatever you do, think delicate, and serve on the side.
