So I read a bit more about Donetsk and Luhansk and while I can see the similarities where
Ukraine = Serbia and NATO = Russia, unfortunately the similarities stop soon when you realize that Kosovo (= Luhansk or Donetsk), establishes a democratic society that includes Serbian minority by default in the government, where Donetsk and Luhansk start banning Ukranian passports, banishing Ukranians, massive antisemitism movements, and basically want to become dictatorships similar to Belarus.
Similarly, Ukranian army is not targeting Russian civilians in these regions and is not banishing them to Russia. There is no displacement of millions of Russians in Ukraine.
If you are trying to say "NATO bombing of Serbia is justified", therefore "Russia war against Ukraine should be too", therefore hypocrites, it does not really work.
Crimea for some reason was annexed, despite leadership in Crimea wanting the same status given to two countries mentioned above.