Hey Lisa M.! Thanks for reaching out. That’s correct, workspace tags and fields are only available on the Enterprise plan, so if you’re switching to the Professional plan, you won’t have access to them any longer.
Once you switch over, your existing workspace tags will still be there, but in a read-only state, so you can’t create new ones, or link them to new projects. If you’d like to edit the tags or use them on new projects, you’ll need to unlink it and convert them into project level tag boards.