So today's Game Awards just revealed a new trailer for Fire Emblem Engage. They just announced an Expansion Pass is coming to Fire Emblem Engage. They just revealed the new Emblem Rings that are coming to DLC are the Three Houses leaders, Edelgard, Dimitri, & Claude (just showed off their pre-timeskip outfits) and Tiki (the younger version and currently the only Manakete Emblem Ring using Dragon Powers). Other type of content mentioned in the Wave 1 info are In-game Support Items, In-game accessories, and the Silver Card. The first wave is going to be on January 20th.
Nintendo just dropped the trailer right now.