Well, the syringe in BioThunderbirdmon's tail doesn't seem like it would be visible from this angle anyway. These do have red on both the helmet and the horn, so it might still be BioThunderbirdmon.
Ghoulmon's army definitely has at least a few species. I definitely see Devidramon. Some might be Boogiemon as they have some sort of staff. Others look like they might be candidates for Phascomon. I can't tell if there might be others.
Coelamon and Whamon (hey, it wouldn't be right to do Adventure without Whamon).
In the holy army, I see Valdurmon, Cherubimon, Ophanimon, Seraphimon, SlashAngemon (cool), ClavisAngemon (YES!!!!!), and Rasielmon. Woof, that preview includes all basic Mega-level angelic Digimon apart from Dominimon. I wouldn't be too surprised if we don't see the entire army here. There are a few other holy Mega-level Digimon they could include that are somewhat angelic in appearance (Gallantmon CM, HolyDigitamamon, Goldramon, Magnadramon, and maybe Azulongmon or other of the Harmonious Ones).
Valdurmon's inclusion in particular is interesting. It's not one of the typical holy Digimon. It's noted as an ancient Digimon as well, which seems like it may play a role in the Adventure: Digital World's past. With the light and dark motif going on, I'd have to wonder if Darkdramon might make an appearance. It wouldn't be the first time to have Chaosmon components animated (Savers gave both BanchoLeomon and Sleipmon, while Xros Wars gave Darkdramon). So this does mean that now all 4 components have been animated at some point. Presumably, there should be at least 6 variants of Chaosmon (4C2) - unless the arms can switch sides, which could make 12 (4P2). This is also presuming that you can't form a Chaosmon using 2 of the same component, in which case that would add 4 new possibilities.
Is it just me, or does that dark orb the Digi-Eggs are coming out of look a lot like the Dark Area or Lucemon SM's Gehenna as portrayed in Frontier?
Tylomon, too, huh? It's nice seeing more of the Armor Digimon getting animated. I wonder if we'll finally get ones like Shadramon who haven't appeared in any of the anime (I think that should also include… Frogmon, Sheepmon, Elephantmon, Peacockmon, Orcamon, Rinkmon, true Quetzalmon, Mothmon, Butterflymon, Owlmon, and GoldVeedramon).