Actually it simply would look like in Crimea. 100% surrender and 70% even changing the side.
Thousands of former Ukrainian soldiers are actually now serving in Russian ranks in Crimea.
They just need to take out the leaders and radicals.
What happened in Crimea and Donbass was different. Those areas were heavily populated with ethnic Russians and Russian-speaking Ukrainians. Ukrainians from Kiev and Lviv are not going to change their loyalty, no matter what happens. Even now, the Crimean Tatars are not happy under the Russian rule.