Can i publish my novel in Japan?

I would like to try to publish my book/novel with a Japanese publisher, but, I don't know if I need a working visa for that, or do I just have to be there in person?

I'm from Mexico so I don't know if there are any restrictions.

Are there any other hurdles I'm not aware of if I want to publish a novel in Japan while being an outsider?

Also, does the language of the novel I want to present need to be in Japanese, or can they translate it?

If the novel is not written in (perfect) Japanese, the most common way to be published should be to apply for some new face awards that accept applications from public.

If not, your novel needs to be published first and known in your country.
The publishers will get to know your work through agents.
Or, in some cases, Japanese translators introduce books to the publishers when they like them a lot.

「I would like to try to publish my book/novel with a Japanese publisher, but, I don't know if I need a working visa for that, or do I just have to be there in person?」

You seem to be under the impression that if a Japanese company is publishing (i.e. selling) your novel in Japan, you need to be in Japan while they're doing it. This isn't true, though. It's perfectly possible to write the novel in your home country, then sign a contract with a Japanese company that will print, distribute, and sell the book in Japan without ever traveling to Japan yourself. If anything, having a novel you wrote published in Japan, by itself, probably wouldn't be enough to qualify you for a work visa anyway, since there's no need for you to be in Japan to do that work.

「Does the language of the novel I want to present need to be in Japanese, or can they translate it?」
Are you asking if you need to provide a Japanese publisher with a completed Japanese translation of your novel before they'll publish it? The answer is no. Publishers hire their own translators.

「Are there any other hurdles I'm not aware of if I want to publish a novel in Japan while being an outsider?」
Yes, I think there are a few.
The important question to ask yourself is "Why would a Japanese publisher want to publish my novel in Japan?"

Is your novel finished and popular in Mexico? If so, Japanese publishers might take that as sign that it could be popular in other countries too, maybe Japan, and be interested in publishing it.

Is your novel unfinished, but you're a famous author, or have already written a different novel that was a big seller? If so, Japanese publishers might be willing to gamble that your next novel will be a big seller too, and be interested in publishing it in Japan.

But if your novel isn't already popular in Mexico, and you're not a famous author, it's going to be hard to find a Japanese publisher at this point in your writing career. Remember that it's a risk for a publisher to publish a book. They're paying the author, and covering the expenses of production and distribution so they need to believe that the book is going to sell enough copies to not only cover those expenses, but also make a profit for the company and allow it to pay its employees. If you're an unknown author from Mexico with a novel that's not popular and/or not finished, it's going to be hard to convince Japanese publishers to take a chance on publishing your work.

The simplest way for a foreigner to get a book published in Japan is for the book to already be successful in its home market. As an example, the Harry Potter series had no problems getting published in Japan because it was already successful overseas, and Japanese publishers thought "Hey, I bet it'll be popular in Japan too."

Maybe another question to ask yourself is why you want your novel published in Japan specifically? Do you think it offers something to Japanese readers that they'll appreciate more than readers in other countries?

Are you asking if you need to provide a Japanese publisher with a completed Japanese translation of your novel before they'll publish it? The answer is no. Publishers hire their own translators.

As a professional translator, I can say that this is not always the case.

If your non-Japanese book is a best seller (in any country around the world), Japanese publishers may be interested enough to hire a translator that they know well.

But if you're an unknown writer with an unknown book in a foreign language, publishers in Japan would have no way to see if the contents of your book is worth publishing here in Japan. They won't know if they can sell enough of it to pay back for their expenses.

So, if you're an unknown writer with an unknown book in, for example, Spanish, make sure you gain a good enough reputation in Spanish-speaking countries first. Then Japanese publishers would be convinced. Or do get your book translated, at least up to half of your book, so that Japanese publishers would be able to read it and see if it's worth publishing. But you have to remember, that the quality of the translation may vary greatly depending on the translator.

So, the short answer to your question is, yes, getting a novel published in Japan is not impossible, but the novel needs to be good enough. Everything can be done through email, so you won't even have to see anyone in person. You can get paid while in your country, according to your country's law.

Are there any other hurdles I'm not aware of if I want to publish a novel in Japan while being an outsider?

Tax. Discuss it with experts once you get to the process of signing the contract with a publisher.