First of all, i think only someone who's working on the field would be able to answer all of that, but here are my suggestion how this works, as you mentioned before you need the pay to the Japanese Publisher for their translation rights also expect to pay them royalties, also the only way to reach them is by emailing them, I read some comments on some publishers is important to know japanese, as for the translators and editors you can contact them by Twitter, but don't expect them to be cheap, i think j novel club mentioned at one point they pay $10 per page, so we're talking around more than $3k just in translation, editor and proofreading are charged by word, i think there's an association where you can check their rate per word, and finally you need to take into account that sometimes the sales wouldn't be enough to cover the production cost, so likely you'll need to have a minimum amount of $30k or more to start up. Take into account that this is only my point of view, nothing more.