Καλώς ήρθες, Αφροδισία!
Not many countries now. If you dig into other questions, such as the perennial favourite What do the Balkan nations think of each other? What are the stereotypes? or What do Albanians think of Greeks?, you’ll see there’s some animus in (FYRO) Macedonia and Albania, and a lot less than there used to be in Turkey and Bulgaria.
Historically, the Romanians would have hated us because of the Phanariotes. But that’s a long time ago now.
When Greeks were new immigrants in the diaspora, they were bottom of the rung, and subject to the usual fear and loathing, especially when they came as young men without families, and thence were associated with crime. That’s Australia in the 1920s, or the US before then. (The main immigration wave to Australia was 1950s-70s, but it was not as predominantly male.) Again, ancient history.