Probably will be situational like a well placed reaper ult flanking from behind and dropping from aboveThing is, seeing her range is roughly that of blizzard she needs to be right in the middle of the enemy team to have it exploited at is full effect. You might think that's what her invis is for, but the delay when she decloaks is really gonna fuck with her i feel.
At that point mccree can flash bang her, rein can Earth shatter her, roadhog can hook her etc. etc. I might be wrong but i can see it actually being really hard for her to get that ult off optimally.