Okay, here's serious reply because no postenings, perhaps will inspire Bernd.
Chiner wants a high speed railway line through Serbia to Budapest (i think she wants it from Grease's ports) for their goods. This is planned for over a decade now but nothing happened. It needs Serb and Hungarian involvement obviously, and there is some French cooperation in it too. So this gives one reason for the visit.
There are other things to discuss, I wanted to hit up Hungarian media to see what they say about Xi's visit here, what were the talking points between him and Orbán.
Wyatt of Defense Politics Asia said something interesting. He believes it is important why Xi went to Belgrade, Budapest and Paris, but not to Brussels or Berlin. The three countries counts the least US lackeys in the eye of the CCP, they are the ones who maintain some relations with Russia (even Macron despite the recent sabre rattling). In case of Brussels and Berlin it's a slap across the face, and EU is not a sovereign state anyway.