It’s always a great idea to have multiple separate backups. Ideally one would use separate software for it as well, but that’s another story.
The restic repository contains of files that are the same regardless where you store the repository. So yes, you can rclone/rsync the repository folder between different places/storages and access/use the repository regardless where it is, as long as you specify the proper repository URL of course.
There’s also the restic copy command, which you can use if you initialized the target repository properly (e.g. using --copy-chunker-params, see restic help init and the documentation for more information). You can copy snapshots from one repo to the other with this command.
A third option, which is what I’d personally recommend, is that you simply do multiple backup runs. E.g. I back up my computer to multiple repositories, by running restic multiple times. So client → server A, client → server B, etc. However, since restic has such good means to verify the integrity of your repository, this isn’t necessarily what you want to do, if you are short on resources.