Update: The game has received an official English localization, available in the international version of the game: https://www.nintendo.com/us/store/products/suika-game-switch/
Hello! This is an English translation patch for スイカゲーム aka Watermelon Game. The patches are in xdelta format and you'll need a couple of things to get started.
First, you need xDelta: https://www.romhacking.net/utilities/598/ and NxDumpTool: https://github.com/DarkMatterCore/nxdumptool
Use NxDumpTool to create a romFS dump of your copy of the game, then get 3 files from your dump. "resources.assets" ; "sharedassets1.assets" ; "sharedassets3.assets"
Copy them into wherever you put your xDelta patches from the download, and patch each file from your romFS dump with the corresponding patch.
Then, we'll make a LayeredFS folder structure to have these newly patched files loaded instead of the original game files.
Folder structure should look like this:
SDROOT\atmosphere\contents\0100800015926000\romfs\Data\ 3 patched files here
Start up the game and enjoy! There is a tiny bit of untranslated text related to date/time on the scoreboard that I just couldn't find, maybe someone better with Unity can help with this.
I did a quick bug check but I'm not 100% sure everything is fine, if there is an issue just let me know and I'll fix it.
Enjoy!