Is it possible that hemochromatosis can go into remission?

With treatment only: This is the most common of genetic diseases. It is a state of iron overload due to increased absorption of iron. It is treated with therapeutic phlebotomy and monitoring of ferritin and iron levels and other testing. If one had chronic undiagnosed blood loss, perhaps one would think they were in remission. But, no, not in remission otherwise.

Yes: Hemochromatosis is caused by genetic predisposition to excessive iron storage. It can be treated with removal of iron- usually by recurrent phlebotomy. If you mean spontaneously go into remission, then usually no, it cannot without treatment. In some cases, though, the iron transport/ storage is facilitated by excess alcohol use- in that situation stopping alcohol will improve things.