I don’t think this is about partition. It’s about NATO trying to create a pretext for settlement along these lines — Russia gets to keep the eastern enclaves and Crimea, peacekeepers go into those regions and border areas to keep the two sides apart while political arrangements are made.
This is how the crisis should have been solved in January before Russia moved in. Then millions of people would not have needed to leave many areas of Ukraine. A lot less damage would have resulted. Now clearly Russia wants a bit more, a land bridge from Donetsk to Crimea. They already have a bridge over the narrow opening of the Sea of Azov that connects Russia to Crimea. There is the issue of water being with-held from Crimea due to closure of a canal that previously transported water into northern Crimea from the Dnieper River.
I don’t know if Russia is ready to give up on Odessa, Kherson and some other areas yet. I hope so. This idea of making Ukraine a very weak landlocked state seems to be an over-reach and will not fly with any other countries. The rest of the world is probably ready to indulge Russia with control of just those three areas, and that’s about it, they should take it and run before they start actually losing those gains as well. Not that they have any shortage of generals apparently, every other person on the street in a Russian city is probably a general without knowing it.
Rather than Polish peacekeepers though, it would probably be better to send somewhat more distanced but competent peacekeepers into eastern Ukraine. Canada, for example, has lots of experience (in Bosnia among other places). Or even neutrals like Fiji which has done some good peacekeeping work elsewhere in the world. We don’t want to inflame this situation, bigger European countries are problematic too. Canada would be ideal because the soldiers while professional probably don’t have very much direct connection to the conflict and won’t be looking to make trouble.
Also, there could only be peacekeepers if there were a cease-fire. Introduction of military forces even under that guise would not qualify as “peacekeeping” and the military units would become combatants.
So if there is a cease-fire, Russian forces are mainly in the eastern and some southern regions now. There would be nothing for peacekeepers to do in Kyiv or Lviv, or Odessa if the cease fire happens soon. They could go there of course, but there would be no hostile forces present so what’s the point of it? The peacekeepers would have to go in between the battling sides and keep them at least a few miles apart as in the Golan Heights or Cyprus or previously in Sinai. Or if it’s more intermingled like Bosnia was, they have to keep everyone slowly moving back to agreed upon end zones, or you get a bloodbath like the India-Pakistan partition in 1947.
Probably the visit of the UN guy to Moscow and Kyiv was a prelude to UN peacekeepers being introduced. This is what happened in Bosnia, although it was really NATO running the operation. The Serbia-Kosovo part of that was an entirely different matter. In Bosnia it was a three-sided conflict involving Serbians, Bosnian muslims, and Croats. It was a very challenging mission and it was done fairly well after some really awful incidents before the end of the fighting there. Nothing is going to be perfect, but this needs to end soon before it does even more harm for no good reason. My guess is half the “russians” in those enclaves would rather not live in Russia and that’s certainly true of Russian speakers in Odessa and Kyiv (and what’s left of Kharkiv which tends to be overshadowed by the mess in Mariupol).