Square Enix trademarks "Tactics Ogre: Reborn" in Japan
A "Tactics Ogre Remaster" was spotted last year in the Nvidia GeForce Now leak, and today's trademark finding seems to line up for a potential upcoming announcement. The Nvidia leak has previously outed other Square Enix titles before their announcements, such as Chrono Cross: The Radical Dreamers Edition and Actraiser: Renaissance.
Based on some of these leaked listings that have since materialized, it seems likely many of the other Square Enix entries in the leak are probably true to some extent, such as a Final Fantasy IX Remake or Final Fantasy Tactics Remaster, though the nature of these unannounced titles is of course uncertain.
The most recent Tactics Ogre title is Tactics Ogre: Let Us Cling Together, a 2010 PSP remake of the original Tactics Ogre strategy RPG. We'll have to wait and see if Reborn is some sort of port, remaster, remake, or a new entry in the series.