First of all, keep in mind that there is a huge difference between localization and translation. Translation is basically the attempt at a 1:1 conversion of words between languages. And quite honestly, if you're on a tight (or no) budget, Google Translate will get you 80% of the way there
Your text in Japanese by translatorpage
まず、ローカリゼーションと翻訳には大きな違いがあることを覚えておいてください。 翻訳は基本的に、言語間の単語の1:1変換の試みです。そして正直なところ、予算が限られている(またはまったくない)場合、Google翻訳は80%の道のりを手に入れます
translated back by different translatorpage
First, keep in mind that localization and translation have a big difference. Translation is basically an attempt to convert 1: 1 of words between languages. And honestly, if your budget is limited (or not), Google Translation gets 80%of the way.
For no-budget, no trusted volunteer project, automated translation is very good at translation of meaning. Not just word by word translation. You can check by translating idioms like "That was the last straw." Part of what you mean with localisation is just good translation. Translating that idom literally like this is the last of that dry grass is not translating the meaning. The meaning is, that an action pushed something over its limit.
Localisation is going beyond good translation. It is rewriting a thing like it would have been expressed by a native. That can also be a temporal thing, if you adapt a theme for modern times, like that series Sherlock did. They did not just refilm some Holmes stories, they made the story believable in modern times, including smart phones and the jokes about them being a gay couple.
The diff in translation and localisation is very apparant in names. To an english native speaker a name like Raven or Stormwind or Steward is something different than to a non-english native. The first is a black bird. You literally are named like the bird. The city has a descriptive name and localised it should be something with strong air currents. And while steward is a name now, in LotR that one guy had that position and a good translation should localize it to the respective title.
Most stuff does not need localisation. Only good translation. Just look at Superman. Or Captain America. Localising them would not go well. (Though people use these terms not very precise most of the time ;-)
In games you have the added problem of your own invented terms and concepts. If you write clear in your own language, automated translation of meaning is good. But if you need knowledge about the story there will be even more things a native speaker should go over. Like that example with mad. It could also mean crazy, instead of angry.
That being said, I think the first step is to actually make the game translateable. If the text is embedded deeply or procedural generated, that is a problem. Some engines are even auto-translateable by third party tools, on the user end.