Transmit invoices with portal upload as preferred delivery method

Summary:

I have setup customer site profile preferred delivery method to "portal upload".

We have some client invoices that need to be uploaded into a client portal in a specific format.

How do we transmit invoices with portal upload, any ESS jobs that need to be run where I can select the specific format?

Are there any other setups that need to be done other than customer site profile setup?

Content (please ensure you mask any confidential information):

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

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