Thanks for reaching out to Microsoft Q&A.
The mass import functionality for glossary terms into governance domains in Microsoft Purview is currently a highly anticipated feature, but as of now, there hasn’t been a specific release date announced for it. Microsoft is continuously updating Purview, and features like this are often included in future updates based on user feedback and demand.
For the latest updates, it’s a good idea to keep an eye on the official Microsoft Purview documentation and announcements.
https://learn.microsoft.com/en-us/purview/concept-glossary-terms
Hope this helps. Do let us know if you any further queries.