There is a quiet confidence that develops as a good player matures. Some get it sooner than others. You have to have an inner belief that you will win every pitch, every at bat, every game, etc. Of course the actual outcome won’t be that way, but you still have to believe that it will. To me, confidence doesn’t include anything that shows up your opponent. Showing up your opponent crosses the line into arrogance - which includes loud self promotion, bat flips, stealing bases late in the game with a big lead, etc. The teammates that I respected the most, and current players that I hold in the highest esteem, all conduct(ed) themselves that way. With a quiet confidence, sometimes bordering on cockiness, but never arrogant.