I want to deploy an event receiver in all of the Document Libraries in my site, the article that I'm following is that the RER is installed to a specific library only Steps to create an event reciever. And also can I register my RER with libraries that have not been created yet because in the article, and base from my experience. The library should be created first before deploying the app so that the app will be registered in the library
You could use PowerShell script to add the remote event receiver to multiple document libraries. We can add a loop in the PowerShell script to loop through all document libraries.
For more detailed information, refer to the article below.