The solution to the conflict seems clear. All countries desire friendly countries on their borders. In this respect, the United States (US) and Russia are no different. When Russia aligned itself with Cuba 60 years ago, the US did not like it, especially when missiles were put there. Even though Cuba was a sovereign country who welcomed the Russians, the US interfered and forced the removal of Russian weapons. Way back in 1823, the US unilaterally invoked the Monroe Doctrine https://en.m.wikipedia.org/wiki/Monroe_Doctrine that insures that both the north and south American continents were US friendly. Simply put, Russia wants the same, but to a much lesser extent. They are not unilaterally invoking a doctrine that insures that both the European and Asian continents are Russia friendly. They just want an easier solution, one that insures friendly nations at its borders, not whole continents. Ukraine and other border countries simply should promise to be neutral and not align themselves with countries adverse to Russia. In return, Russia would respect Ukraine's borders and those of other countries on Russia's borders, and not invade them.
And there's more: (1) Russia would go the extra mile by pulling back its military forces away from the border a distance equal to the pullback on the other side. With respect to military exercises, (2) Russia would in a similar fashion, refrain from conducting military exercises at distances commensurate to exercises from others. In this fashion, Ukraine keeps all of its land, a treaty not to be invaded, and a pullback of military forces. And Russia takes a position like the US in which the countries on its borders are friendly, are void of military forces, and where no military exercises are conducted. This is truly a win-win solution.
Playing war games near one's borders with bordering countries that are not aligned with you and expect there not to be tensions is a fantasy. How would the US feel if Russia aligned itself with Canada or Mexico or any of the Carribean countries and then conducted war games? China and North Korea are looking to see what happens since they too don't like war games played along their borders either.
The diplomatic secret to global peace is mutual respect. Treat others as you would like to be treated. Like the Bible says, do unto others as you would like others to do unto you.
It is really that simple!