When doing a pre-migration check or copying objects, the following message is displayed:
Copying the content from a MicroFeed list is not supported.
Copying the content to a MicroFeed list is not supported.
A SharePoint Microfeed list stores user-related activity in the newsfeed, such as replies or comment likes. For more information on microfeeds you can watch this video.
Unfortunately Sharegate does not support migrating the content contained in the MicroFeed list at this time.