Not sure of pre-1900 (or even post-1900) PODs involved though what if Hungary (up to the present day) had access to either the Adriatic or Black seas?
1) /pre-1900; more success against Ottomans results in subordination of Wallachia to Hungary, with or without being entangled with Austria. This produces a vulnerable salient that both Russians and Ottomans will try to seize, and also buffers the Balkans from Russia. How resistant the Romanians are depends on details. But Romania is Orthodox IIRC so that is a flashpoint.While Hungary having access to the Adriatic seems feasible, how would it gain access to the Black sea?
Not sure of pre-1900 (or even post-1900) PODs involved though what if Hungary (up to the present day) had access to either the Adriatic or Black seas?