Is there a reason to use Fireball instead of the anti air grab which does more damage and leaves them closer to you??
Well Sheeva actually has 3 choices.
1. Enhanced Low grab, b2, 1+2, Fireball. Easiest Timing of the 3 with 45% damage and sends them far across the screen to continue fireball/ground pound zoning. Good for characters like Johnny Cage who you want far away from you. (Do not do this one if your opponent is in the corner. The fireball will wiff.)
2. Enhanced Low grab, b2, 1+2, Air grab. Slightly harder timing than fireball for 47% damage. This keeps opponent close to you in an untechable knockdown state where they can't roll away but they can still wake up attack. Good for characters you have a hard time with their zoning like Shang Tsung.
3. Enhanced Low grab, b2, 1+2, BF3 (grab 'n punch). Super Strict timing (I deem too hard for tournament play) for a whopping 51%. (unless your in the corner, if so the low grab puts your opponent in the corner and you can do this one with ease.)
If opponent is jailed blocking low then don't do the enhanced version of the low grab (we only use the enhanced low grab for armor, not for the extra 4% damage) do the normal low grab. The damages for each are
1. 41% damage non enhanced grab. Same properties. Puts opponent far away for more zoning. Don't use if opponent is in corner.
2. 43% damage non enhanced grab. Same properties. Untechable knockdown, no roll but opponent can wake up attack. Keeps enemies close for more pressure.
3. 47% damage non enhanced grab. Same properties. Still only use if you are in the corner for easy timing.
Edit: I just tried adding a NJP after all 3 of these options. It works for all 3 enhanced and non enhanced ones. Adding 2% damage to each option. The difficulty is way harder and totally not worth it in my opinion.