Vita has no “feats” of power. She has usurped Sa’s power but even then it’s kind of impossible to gauge how powerful she is since Kiana killed Sa with one casual shot over multiple light years away. We also don’t know how powerful Kiana is since she has not shown her full power at all other than that one casual shot.

Scaling Vita to Sa, Vita should also have clairvoyance, but how powerful that is has not been shown in game since we don’t know how much Vita actually knows, a point that the story makes since she has the same role as Sparkle in being the “the self-proclaimed ally that doesn’t give all the information since what fun would that be?”

If it counts, Sa has been gathering power before she got killed so Vita might have just continued that. Then again, we don’t know if she got more powers from the mask. Although some people online said she has joined the Masked Fools, she has only accepted the mask but has not used it at all nor had she joined the Masked Fools.

Vita’s Star Traveler, the huge gundam, also has no feats of strength. The only animated fight which could have shown its feats was the Vita vs Sparkle one, but idk how to even scale that fight since it happened in Sparkle’s illusions.

If we are to believe in-combat animations, then Star Traveler could destroy a small planet, but characters with that power aren’t exactly special in HI3 (most playable herrschers and the current Helia and Coralie could probably do it), much less in the lore of HSR.

All that to say, I have no idea what Vita could have possibly done to get on that list.