I believe you won't find a single person who would take the responsibility of a definite answer to that.
I do know that they are going to wonder just how is your wife going to sponsor you (and this means "support financially") when she's just a student in UK and you're in Japan. They will also question your intentions to stay married to her when there are plans to put about 10 000 kilometers between you two. Doesn't exactly fit the image of marriage... of any culture.
Perhaps to try and see (and to include a carefully worded letter explaining your future plans together in Japan, and how your temporary separation is "painful but necessary part of preparations to that" or something something) is the best option. Your previous failed applications are not held against you like in the US, so you can try again once your situation is clearer.
With a
quick googling, I found several cases where spouses of Japanese nationals opted other than a spousal visa for various reasons. Not me, though...