We've been using sharing at the Flow level since it was added in September 2018 (check the changelog). You get to this option from the kabob menu on the individual flow:
![Example of the sharing option in the Flow menu]()
From there, you'll get a sharing menu you can use (keep in mind, you can only share with people who are in the project and have suitable permissions):
![Flow-level sharing dialog]()
From there, you can see either all flows by default or just those that are shared:
![Flow ownership sharing example]()
Note that there's currently only one shared permission level, which is Collaborator. This means the person you share with can work with the flow, add recipes, etc.—but they don't have the option of renaming the flow or managing sharing. The recently added Folders option doesn't support sharing at all.
Full details on sharing flows can be found here:
https://cloud.google.com/dataprep/docs/html/Overview-of-Sharing_118228675