Does not seem sensible. Most Ukrainians that are exiting to Russia are likely already very Russian. When things finally settle in Ukraine, if Russia gets what it wants. I think the plan would be to get those folks back to Ukraine. Particularly in the Donbass region. Ukraine is quite West/East split as to Ukraine majority areas versus Russian areas, as far as the people’s ethnicity and ethnic leanings go.
It is more likely for the Russian folks to want to and be able to get out of the war zone to the east, if Russian forces are in control of the possible escape routes.