Yes. You just create a VMM domain with the exact same name as the existing vDS. The legacy vDS needs to be deployed within a folder under the DC with the same name. Other than that, shouldn't be a problem. You can do the same with EPGs/Port Groups - take control over existing ones assuming you match the names.
Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: