I can't speak to the spouse visa but as for other issues. There is a lot to consider when being in a relationship with someone from a different culture and whose native language is different than your own. My advice is to make sure that you have talked over everything and make sure that you, in general, have similar ideas/opinions about what your expectations of the relationship will be. Make sure you talk about what your expectations for each other may be, talk about money, talk about kids and how you want to raise them, talk about visits to family, talk about where you will live long term. I'm guessing that you are of typical college age and I know how, at that age, you don't have a lot of life experience and relationship experience to go on. I hate to mention them because I have mixed feelings on them but it may be worth seeking out one of the "relationship compatibility guides" that exist. They are basically a list of topics that you can talk about with your significant other in order to find out what each of you thinks about those topics. The benefit of a guide like that is that there are likely topics in there that wouldn't have ever come up in normal conversation that may be very important to one or both of you and that you may have very different views on. Please realize that I am not trying to be a naysayer to discourage you and there is no such thing as a perfect relationship. Relationships take work and there will always be ups and downs but the more information you have going in the better. Also, when you have those discussions be very honest about how you feel or what you think, it will defeat the purpose otherwise.
You also will want to make sure that you are learning Japanese and are actively working on becoming proficient, you will need it in order to be able to accomplish things without your wife having to chaperone you in order to translate. Be prepared for a different work culture as well, though you likely would be adapting to that anyway, as you are still in college, it might be far different than you expect.
Good luck, I wish you all the best!
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