I'm interested in the kirikiri engine, what tools should I use?
There are many tools available for kirikiri engine like if the game is not encrypted you can simply extract it with any kirikiri unpacker like KAGTools or if the game is encrypted you can use garbro to select the encryption method then extract it, repacking can be done with garbro as well so you need not to worry about where to find tools, Kirikiri engine game files can be both unpacked and repacked with garbro.
For script you can extract the scenario folder of data.xp3 archive the
Scenario folder contains .ks or .scn files that are plain text files so you can extract
Just directly commit the changes in the file but I advise you to use Vntranslationtools to import the files text to .xlsx file as it makes easier to translate. If you need to edit menu and cg's you can just extract the images and edit them directly because most of the kirikiri engine uses .png as images so there no need to worry about converting the image in png then convert it to the format the game uses.
Also some kirikiri engine uses .tlg as images and I have got no clue about it even though I tried to convert the png images back to tlg it didn't worked out.
To make a patch for the game without making changes to any original file you can just create the new xp3 archive as patch.xp3 and the game will accept it to overwrite the original files in most cases.
If you have got any more question, then please be specific next time as I have wrote mostly everything you need to know to translate a kirikiri game.
Also as this thread is not meant for tutorials you should PM me next time otherwise you can mention me in a thread of tools and tutorials.