I wouldn't say that Austro-Hungarian co-productions were really the norm, but they were certainly a norm at the time, alongside productions that were made exclusively in Budapest or in Vienna. There was no sudden switchover in the movie sector after the dissolution of the Austro-Hungarian Empire, so that the years 1919 to 1923 are marked largely by a continuation of established practices from prior to that date. In terms of production, that meant that there continued to be wholly Austrian and wholly Hungarian productions, in addition to co-productions. Changes in the distribution sector were similarly pretty gradual during these transitional years, with specifically Austro-Hungarian distributors such as Österreichisch-Ungarische Gaumont, Monopolfilm H. Engel (which handled many of the horror/fantasy features of the period), Nordisk Film Co. Budapest-Wien, Stuart Webbs-Filmvertrieb für Österreich-Ungarn (which distributed DER JANUSKOPF in Austria and Hungary) and others all maintaining their pre-1918 operations until 1922/23.
There had always been a certain amount of blurring of strict boundaries too. For example, although all of Béla Lugosi's 1917/18 pictures under the pseudonym Arisztid Olt were shot in Hungary, their production company referred to itself as 'Star Film of Budapest and Vienna' and issued all the movies simultaneously in Hungarian- and German-language versions with unique titles for each language, making them truly Austro-Hungarian 'Hungarian' pictures, so to speak. Likewise, a number of Hungarian filmmakers readily shot scenes in Austria and vice versa both prior to 1918 and during the 1919-1923 'gradual transition', a mildly-line-blurring category into which DRAKULA HALÁLA also falls... though it surely wasn't a co-production by any stretch of the imagination, maybe just possessed of a little 'pre-dissolution residue'.