So, the position is not the same even if Col: count is same because the line contains some Zenkaku chrs.

I don’t know Japanese; please forgive me if I’ve missed the point in some way.

The column (“col:”) in the status bar is just a count of characters from the beginning of the line, starting at one. (That’s not even always what you might expect; combining characters that form a single visible character are still counted separately.)

Aside from a few things like cursor positioning, line wrapping and selection with the mouse, Notepad++ (like the Scintilla control it uses for editing) doesn’t concern itself with the physical space occupied by characters. In English, we can use a proportional font, and a line of twelve characters will show the next “column” as 13, whether they are IIIIIIIIIIII or WWWWWWWWWWWW.

So (though I haven’t attempted to test it), regardless of font, I would expect that there would be no recognition of the difference between half-width and full-width characters.