I didn’t agree with what took place in the 90s, but I do not see that as an occupation and annexation either.
Crimea was clearly different. Russia marched in and annexed it.
That was indeed an annexation by the European Union.
And it started with Helmut Kohl recognizing Croatia and Slovenia, even against US policy at the time.
This conflict was a prelude to the eventual 2007 “enlargement”, which gave the EU access to the Black Sea.