How to automatically rename a lot of folders and files?

I'm trying to upload / copy thousands of folders and files to OneDrive (as a backup).

Unfortunately my naming convention is proving a problem for OneDrive and I am getting 100s of error notifications, saying that items can not be uploaded. A lot of my folders start with a space. And OneDrive can't deal with that:

Is there a way I can automatically rename thousands of folders and files, so that I can replace the space with say a hyphen (to keep the files at the top of Finder windows when sorted by name).

And then search and replace files with any of the other offending characters?