Imagine the strike zone was just convention and pitchers were technically allowed to roll the ball if they were more bothered about preventing home runs than getting the opponent out. Think your baseball mind would be annoyed when someone did it, and the lawmakers would have to step in pretty quick to stop it being a regular thing...
(Think there's also a general prejudice against underarm play in professional sport as it's for kids who can't throw properly and feels like mockery. Underarm serves in tennis are frowned upon, even though an alert opponent has plenty of chance of scoring a point from them)
I don't think there's a rule against rolling the ball to a batter; it would be called a ball. It would be similar to a wild pitch or an intentional walk (when you had to actually throw the 4 balls).
I'm beginning to feel like Americans trying to understand cricket trying to understand the tactical permutations of intentional walks :D
The equivalent would be bowling a ball rather than a strike in a baseball variant where each innings ended after a fixed number of balls regardless of the number of outs (which is effectively what One Day variants of cricket are). Specifically, walking the batsman when they needed to score a home run or at least a double. I think fans would get upset!
Watch softball sometime.
I mean this does exist in baseball, kinda, but there’s incentive to not do so since it gets the opposing team closer to scoring: https://www.mlb.com/glossary/standard-stats/intentional-walk