As of April 2020, it does not fire the 32-bit message when installed in the sub directory : C:\Program Files\Notepad++\plugins\NppTextFX\NppTextFX.dll but, some functions (Sort...) do not work, while others like Delete blank lines raise an "Acces violation" making N++ hang.
As of April 2020, it works like a charm. Just put it in a sub directory : C:\Program Files\Notepad++\plugins\NppTextFX\NppTextFX.dll