I have an Anova generation 1 (the original, built-like-a-brick-shithouse model), and it's switchable between centigrade and fahrenheit, and it works fine in Japan (100 V, 50 Hz).
On the other hand, sous vide is overhyped. Like slow cookers and pressure cookers, you'll find it's good for a very small number of things. For me, being able to make onsen tamago eggs is the one thing I use it for now. If you like super rare meat, it's good, but why does the temperature of the entire slab of meat have to be the same exact temperature? In Japan we can eat beef, and even chicken, raw, because of better sanitation controls in production, so we just cook meat lightly if we like it really rare. And sous vide vegetables are just a waste of time. Summary: There's a strong placebo factor at work among sous vide advocates.