I have written my own fucntion.

You can test it with:

SELECT dbo.Format_RemoveAccents( 'ñaàeéêèioô; Œuf un œuf' )

You will optain ==> naaeeeeioo; OEuf un oeuf

The function:

CREATE FUNCTION dbo.Format_RemoveAccents( @Str varchar(8000) )

RETURNS varchar(8000)

AS

BEGIN

...