About the only, marginal chance of this happening is if we happen to redefine the meaning of Yugoslavia. Say, the breakaway state of Slovenes, Croats and Serbs doesn't wind up as part of Serbia (there were some shenanigans there OTL; still very difficult, but I suppose it's within the realm of possibilit) and manages to keep both ySerbia and Italy away, retaining much of their core territories, albeit somewhat reduce. That alone is very, very difficult, the territories weren't any more up to continuing WWI than anyone else, but I suppose both Serbia and Italy would've been exhausted. Near-ASB, but by some miracle they manage to pull a Turkey and survive.
The resulting nation renames itself Yugoslavia (the name was bandied about at the time, along with several others). It's a divided mess of split loyalties and ethnicities that, much like Austria-Hungary, keeps stumbling onward for year after year. Ultimately, in some desperate bid to give the nation some semblance of unity, they try appointing the last Habsburg heir to the throne, leading to a Habsburg restoration. Whether that works is anyone's guess, but it's likely to make enemies of everyone in the neighbourhood ... of course, our hypothetical Yugoslavia already has enemies everywhere, so that's not much of a change.
EDIT: Just to clarify, I don't actually consider this likely and unless we're dealing with a very, very good writer, I'd punt such a TL to the ASB section.