This would just be speculation at best. There haven't been any hints that she'll be coming with a stage, and even if she did, what stage would it be? Greece is already covered stage-wise, and her story on the timeline of 1583-1590 wouldn't have her anywhere else other than Greece, because she doesn't journey for the first time until SoulCalibur II, which SoulCalibur VI's story leads up to but doesn't start. 2B's stage isn't on ranked because it introduces performance issues, apparently. So unless any additional stage was less technical (no background animations, I guess), then it's not likely it would go on ranked either.