This video shows you how I used Polybrush to place vegetation in my project “Ruined Atrium” here the link to Artstation!
https://www.artstation.com/artwork/QrB6mZ
Here the package in the Unity asset store and the Artstation Marketplace:
https://www.artstation.com/a/23415
https://assetstore.unity.com/packages/3d/environments/jungle-tropical-vegetation-178966?aid=1011lfysW
source