Please excuse my abrupt contact. I am a Japanese who creates mod translations and patches as a hobby. To be honest, there are a lot of people who are reluctant to help me because of the lack of Japanese language support. Since I have made a Japanese translation patch, I would like you to make it easier for people who are new to using it to get started. But honestly speaking, it is not that burdensome since all you have to do is add ja_jp.json to the lang folder. We hope you will consider this opportunity.
ja_jp.json

Upon checking the file, some things look good, but there are a lot of lines that are missing, or done wrong.

SEE:
https://github.com/sakura-ryoko/litematica/blob/7a8848bf56707940453f68a6ea2e30f98c136dce/src/main/resources/assets/litematica/lang/ja_jp.json

MISSING/EXTRA/MALFORMED Keys (Temporary file):
https://github.com/sakura-ryoko/litematica/blob/7a8848bf56707940453f68a6ea2e30f98c136dce/src/main/resources/assets/litematica/lang/ja_jp-extra-lines.json

I kept the other lines as a separate file that needs to be fixed so that it can function properly within the mod. The actual translation Keys are now added to the ja_jp.json file in english that are missing, and needs to be updated / translated.

NOTE: This is the active DEV Branch for Litematica Snapshot 24w39a, which includes translation keys for all of the config comments and names. There are also lang files located in all of the other mods, such as MaLiLib, if you want a complete translation:

https://github.com/sakura-ryoko/malilib/tree/17ed6556a7637b03338a6ac598040120b5d28723/src/main/resources/assets/malilib/lang

If you are able to Use the PR system, please do so; if not, just post the updated files here. Once this work is completed, I can copy the finalized LANG files to 1.21 as well.

Of course, I can finish the translation using scripts or Machine Translations (Google, etc); but that ultimately can do your culture a dis-service, especially for this amount of changes.