Adding Files or Folders to A Vault - Copy or Move?

Well, I guess that’s a question for what purpose you want to use Cryptomator.
In my case the vaults are just for online backup purposes. I’m not working directly with the files in. So I of course copy the files and do not move them.

By the way: you could be interested in this thread and why moving files into a vault on windows is technically nothing else than copy them and delete the „original“

And last but not least: Cryptomator is designed for online storage purposes. If you „just“ want to encrypt your local files, you might want to consider tools that are made especially for this purpose, like veracrypt.