Her kit needs some seriousnwork to be viable, IMO.
Passive should hold up to more than 1 grenade.
Tactical doesn't seem to slow enemies enough and should be wider or larger (round instead of rectangukar?) It can be slide jumped over fairly easily and is far too easy to get over.
Ultimate doesn't block Seer's scan and I thought that was the point, too. If you throw it and a Seer throws their ultimate right next to it, you actually have put your own team at a disadvantage where they can see you but you can't see them. Personally I think it needs to stop enemy bullets, grenades, and abilities like Mei's ice wall in OW2. You might need to limit the length of it if you did that because as it is now it can be huge.