If you're having trouble beating Ego 80 consistently, you can always play at a lower ego like 70 or 75 and then forfeit some games at 99 to bring the average up (as long as you don't miss the playoffs doing so).
Edit: Dantares says you can win 9 games at 67 ego and forfeit 7 games at 99 ego in the regular season while winning 2 games and forfeiting 1 at those same egos in the playoffs and that's good enough to get the achievement. Try to win games against people in the same conference though so you don't risk missing the playoffs.
It's going to take time getting used to timing and aiming your swing at higher difficulties, but here's some miscellaneous tips that should help you win games:
- I'd recommend using a power hitting team (like the Sirloins or Nemesis) over more pitching or defense specialized teams. In this game, it seems good hitting > good pitching.
- I'd also recommend using the power swing almost every time. The difference between the games I used contact swings only and power swings only was very noticeable.
- Try to "paint the corners" with your pitches, especially breaking balls (non-fastballs). That means aim your reticle outside the strike zone but make it so that the arrows point over a corner of the strike zone. You can strike out a lot of batters doing this.
- When there's a runner on 1st base, try to throw low pitches. Batters often "get on top of the ball" and hit a lot of ground balls which you can then turn into a double play. [This tip and the previous one are just common baseball knowledge when pitching in real life but I'm pretty sure these strategies affect CPU batters as well because CPU pitchers have done both of these things to me frequently]
- The Wild Pigs have a catcher with a pretty weak arm. Playing against them, be sure to steal when you've got a fast player on 1st base.
- Try to bat with your pitchers as little as possible. Sub in a pinch hitter when your SP is tired or when you've got a RP at the plate.
- When you do have a pitcher at bat, try to draw a walk. The CPU doesn't seem to treat pitchers as easy outs and often pitches outside the strike zone like they do with other hitters. You could try to intentionally foul off pitches if you've got good timing and then wait for more balls outside the zone.
- When increasing your ego to a difficulty you aren't that comfortable with, try to first do so against a pitcher with a low velocity. They seem to be the easiest to hit off of.
- When fielding a ball, make sure to hold the button of the base you want to throw to before you even get the ball. This saves a lot of time when trying to throw out runners and a lot of pennant race players for some reason don't do this.
- When facing a pitcher with high velocity (on 80 ego), I like to start the power swing right around when the pitcher releases the ball. The lower the velocity rating, the later you start the power swing.