There's not much to go on from the tease, as it showcases a very short animation of the franchise's Mark of Erdrick, captioned with the short phrase "The legend of Erdrick draws near". Crucially, however, we do get confirmation that the game will be heading to the Nintendo Switch in addition to Steam, Windows, PlayStation 5, and Xbox Series X/S.
It sounds like we might be getting a fresh announcement soon, then, possibly for the game's release date. It was originally announced all the way back in May 2021 with very little information to satiate fans since then. The last communication we received was in September 2023 during which series creator Yuji Horii stated that development was "progressing quite steadily".
Square Enix has been utilizing the HD-2D art style liberally in recent years, with the likes of Octopath Traveler II, Live A Live, and TRIANGLE STRATEGY all showcasing stunning visuals.