Move/Copy document or item from one site collection to other site collection

Enable workflow elevated permissions

Below are the high-level steps to do enable the workflow:

1. Allow the workflow to use app permissions in a SharePoint Server 2013/Online site.
2. Grant full control permission to the workflow.
3. Wrap the call action inside app step.

• Go to Site Settings, under Users and Permissions, and click Site app permissions.   
• Activate the Workflows can use app permissions feature 

Refrence:

https://docs.microsoft.com/en-us/sharepoint/dev/general-development/create-a-workflow-with-elevated-permissions-by-using-the-sharepoint-workflo