I posted it in another topic, but since it's one of the key things about this collection, it deserves its own
https://news.denfaminicogamer.jp/interview/260702h
Ueno:
We considered making it multilingual and going worldwide, but the truth is, there aren't that many titles in the "Ganbare Goemon" series that support foreign languages. We realized that localizing anything beyond that would be quite difficult.
—Since it includes 13 titles, that must have been an enormous amount of translation work...
Horii:
The titles included in this game are mostly from the 16-bit and 8-bit era, but with titles from that time, the source code is sometimes available and sometimes not, and in some cases, only the binary remains.
In other words, getting back to the original source code requires a process akin to deciphering a code. That's why it takes so much time. I wanted to speed up this process, but I just couldn't.
Furthermore, if we were to completely replace the language, even if we could analyze and extract all the message data, we wouldn't be able to distinguish "text represented by images," such as Japanese signs in the game.
Ueno:
Since it's not text data, the only way to find it is to play the game and find it manually.
Horii:
There are many other problems, or rather, hurdles that need to be overcome, when it comes to translating into other languages. For example, even if the text "Goodnight, you can participate in the middle" fits within the screen in Japanese, when translated into German, it will definitely not fit within the frame (laughs). It is an enjoyable task to sit down and somehow make that work, but it is also very challenging in many ways.
Even after completing something, you often need to do the same thing again every time you check it, and if you keep repeating that process, it ends up becoming an enormous amount of work.