While the ShareGate migration tool supports navigation by term, it does not correct the URL property of a term's Simple Link or Header during a migration.
Note: Since this limitation involves URL correcting, this limitation only affects migrations with different managed paths.
The links for terms with navigation node type Simple Link or Header are broken following a migration.
In SharePoint, the navigation node type Simple Link or Header allows you to set a URL for the terms you use as part of your site navigation. Together these terms can create your SharePoint taxonomy---the classification, categorization, and hierarchy of your content.
For more information, see Microsoft's Introduction to managed metadata.
During a migration, the ShareGate migration tool does not change the URL in the Simple Link or Header field, so links are not corrected for new destination paths.
It is possible to manually update the destination term properties in your SharePoint site settings.