Although they have not thrown an MLB pitch in 2023, Andrew Heaney threw 12,003 pitches that were tracked by the PITCHf/x system between 2014 and 2022, including pitches thrown in the MLB Regular Season and Spring Training. In 2022, they relied primarily on their Fourseam Fastball (93mph) and Slider (83mph), also mixing in a Change (85mph). He also rarely threw a Curve (80mph).
In 2022, compared to other LHP:
His fourseam fastball generates an extremely high number of swings & misses compared to other pitchers' fourseamers, has some natural sinking action, has slight armside run and has slightly above average velo. His slider generates a high number of swings & misses compared to other pitchers' sliders, results in somewhat more flyballs compared to other pitchers' sliders and has some two-plane movement. His change generates a very high amount of groundballs compared to other pitchers' changeups, is slightly firmer than usual, has slight armside fade and has some natural sink to it. His curve (take this with a grain of salt because he's only thrown 16 of them in 2022) is basically never swung at and missed compared to other pitchers' curves, is much harder than usual, results in more flyballs compared to other pitchers' curves, has little depth and has slight glove-side movement.