Historically, these fonts were required because standard versions of Arial did not include the full range of Azerbaijani glyphs. Today, modern Unicode fonts (like standard Arial) usually include these characters, making "AzLat" versions less common but still useful for legacy documents.
There is no single font officially named "Arial Azlat," but rather this refers to a specific configuration of the standard Arial font family used for Azerbaijani or Turkish languages (which use "Azlat" script).