The plugin is the same for the JAP and EUR version, since the codes also work with the USA game the plugin will be the same so you need to copy one of the plugin folder (ex: plugin folder inside the EUR folder) in you sd card and rename the title id with the USA one
If it doesn't work I'll make a new .7z file with everything but it should work
You need to put the plugin folder located in USA/plugin in the root of your sd card, then launch NTR & Kirby, you should have a flash green screen at the 3DS Logo then in game press select to open the menu