Hi @Rush, Jason,
Thank you for posting in this community.
No, it is not possible for an API application using delegated permissions to invite another API application that uses client credentials to access a folder.
As described in the document you provided, recipients can only accept a set of users as parameters and cannot accept an application.
If you use delegated permissions, you can only send a sharing invitation to a user and then access the files that the user has permission to access.
Hope this helps you.
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