Adobe Sign - Add files from Adobe Cloud?

I can't add files from Adobe Cloud to the "add files" field within Adobe Sign under the "more options" selection. I only have the option to take files from my computer itself, which is strange to me, considering it's all Adobe.

I am trying to access the receipts I'm scanning with the Adobe Scan app on my phone, which are automatically saved to Adobe Cloud. I can access these scans on Adobe Acrobat via Adobe Cloud on my laptop, but it seems if I want to use attach these files to the Acrobat Sign doc on the "more options - add files (drag files here)", then I have to download them to my laptop first. It seems to be a lot of extra steps for something that should be integrated via Acrobat. Am I missing something obvious to fix this issue?

The only thing I see aside from adding files from my laptop is the "Library" option that only has templates in it. Can the Library be integrated with Adobe Cloud or Adobe Scan?