When you manually select a Localization in a normal installation of Notepad++, it copies that localization XML file from the Notepad++ executable directory’s localization\ subfolder, and puts it in %AppData%\Notepad++ ↗ as nativeLang.xml.

So if you are installing Notepad++ on many user’s computers, after you follow the normal installation process, you can copy c:\program files\notepad++\localization\russian.xml into %AppData%\Notepad++\nativeLang.xml before they run Notepad++, and the Russian localization should be selected for them already.

edit: for more on config file locations, see the official docs: https://npp-user-manual.org/docs/config-files/

I would like to find a solution …

No localization is chosen after a fresh install until one is selected in the box I red-circled.
It doesn’t matter if there is only one file in the localization folder area.

Side note:

• Until a localization is chosen, Notepad++ isn’t even using English.xml, it is using the English that the user interface is designed in (in the resource files of the project), which happens to be English.

• So if you have a fresh install, and you go to the Localization preference setting above (which will already say “English”) and you drop down the box and re-select “English”, you will see slight changes occur in the user interface!

(end Side note)

You may be able to “hack” something together to get your goal achieved, but I don’t think it can be “automatic” like you seem to want.

But maybe some others have some ideas for you?

I make setup with only Russian language.

Not English. And i have Russian language by default, but i don’t understand why new users has English.

Folder with Localization doesn’t has English. But new users see English, like your photo.

Have you actually selected your flavor in the place you specify Localization ??