24C- Direct apply partner integration

Summary:

Looking for more details on Direct Apply partner Integration

Content (please ensure you mask any confidential information):

1. Can we use Direct Apply with an existing partner integration or does it need a new partner integration? 
2. Radancy (not a marketplace vendor) posts jobs to sites like LinkedIn. Can Direct Apply be used in this case?
3. What are all the applications/ websites that support Direct Apply? 
4. Are there any demos showing how this feature works?

When this feature be actually used? ref#

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):