NJLA is the first place that comes to mind when searching for a suitable Japanese translation program. Most people join a Japanese language translation course to gain suitable employment in the field of translation, localization, or interpretation. All three of these job functions are different and provide very distinct career paths but are often confused.
Localization is the adaptation of the language that can be easily understood by the other culture, locale, language, etc. A translation is only a small part of localization as it means making suitable changes to the content at times so that it is relevant for the other population. Localization regularly happens for the manga, anime, websites, software, video games, etc. as they grow popular. This may at times require an explanation of the scenario more than done in the original to make a nuance of the character or a situation understood by the other culture.
Interpretation happens in real-time and is usually done orally. It can be between two people or a group and could be in a stressful and fast-paced environment. Interpreters who we see working generally are present at large meetings where many participants from various countries are discussing, like at the UN-level meetings.
A translation is changing one language into the other without changing its meaning or adding anything to it. For instance, if you are changing a short story, website, manual, brochure, website, presentation, etc. from Japanese to English or vice-versa, only the language will change while the content remains the same. Translation focuses on information and skills one would require to interpret as well as for any localization work.
Japanese translation courses usually only focus on the translation part. To gain employment in the other two job profiles one shall need to be not only conversant of Japanese but also be proficient in it by completing the N5 level JLPT test. Passing this level of the JLPT requires very hard work and a lot of patience and self-control.
One can be an expert in two languages, with the ability to read, write, and speak both languages. Being a perfectionist helps but is a basic requirement to be a successful translator. They need to be extremely meticulous and have a very wide vocabulary so that they do not settle for the second-best word.
Most translators work either with a third-party employer or mostly as freelancers and need to manage and dedicate enough time on their skills to get large jobs. If they lose focus or procrastinate then they will have a very hard time meeting a deadline as well as produce the desired quality of work. Deadlines missed in this line are a death knell to any career irrespective of your experience level.
And one may never stop studying even if you were the top-of-the-class at your Japanese language translation course in this career. A Japanese translation program will only teach the basics while you shall need to keep researching and stay on top of any developments in two languages that you translate at all times.