A lot of “ethnic cleansing” is coming. Many Germans are going to leave East Prussia, Pomerania and Silesia ahead of the Red Army. To some extent, it’s just a matter of them not coming back. The Sudeten Germans are going to be kicked out of then Czechoslovakia. The Hungarians will be ejected from Transylvania, so the Soviets can have Moldova. Other than Yugoslavia, the ethnic causes of WW2 will be addressed, in a rather drastic manner.
After WWI there was also population movement. Greeks out of Turkey comes to mind.
In each case the receiving country assimilated the refugees. This is unlike what happened to the Palestinian "refugees" after the Israeli War of Independence. In what I believe to be one of the worst human rights violations of that troubled century, the Arab states refused to assimilate their fellow Muslims, creating a perpetual stateless class for purely political purposes. And the blowhards at the UN not only refuse to condemn this, they actively aid and abet it.