Monolift Soft's new game is codenamed "Legacy" according to Midori.
When I think of legacy, I don't think as much about "the first" of something as much as I do honoring the first of something with something new that is like it.
Xenosaga was their first thing. Maybe a sequel to that?
Or, the game being as old as it is, a Xenosaga 1-3 upscale remaster to refresh us all (or for people like me who never played any of them) snd then they announce Xenosaga 4.