>>23534063
Witch s2
Delta movie 2

Speculating these two just due to the base game staying so close to canon, rather than going in their own direction.

Getter Emperor boss fight due to the ending.

New series is very hard to guess.

Gquuuuux is possible due to oddly not being in DD, just like GWitch missing from there pointed to them keeping it for a console release.

Gundam X maybe due to the anniversary? It also could fit well if we're going to the Emperor's timeline/Axis drop timeline replacing the mega colony drop in the backstory.

Maybe the Hi-Nu but with the Heavy Weapon System attachment to make it stand out from 30's?

There was also that Chinese rumor about a new Mazinger that ended up dropped in development. In the Getter Emperor future scene, they do mention new Photon engine robots.

>>23534120
Maybe based on the Gurren Dan Lagann toy? It'd even be technically a new addition.

>>23534182
Might Gaine got an official design for a Black Great Might Gaine now, but it's basically just a color swap, so it's not like it'd be a big new addition.