Seattle Mariners
Although they have not thrown an MLB pitch in 2024, Wei-Yin Chen threw 17,214 pitches that were tracked by the PITCHf/x system between 2012 and 2019, all of them occuring in the MLB Regular Season. In 2019, they relied primarily on their Fourseam Fastball (92mph), Slider (86mph) and Curve (74mph). He also rarely threw a Change (84mph) and Sinker (90mph).
In 2019, compared to other LHP:
Their fourseam fastball is straight as an arrow, has some natural sinking action and has essentially average velo. Their slider generates fewer whiffs/swing compared to other pitchers' sliders, has short glove-side cut, is much harder than usual and has less than expected depth. Their curve has a sharp downward bite and has slightly below average velo. Their change is basically never swung at and missed compared to other pitchers' changeups, has surprising cut action, results in more flyballs compared to other pitchers' changeups and is slightly firmer than usual. Their sinker generates an extremely high number of swings & misses compared to other pitchers' sinkers, is an extreme flyball pitch compared to other pitchers' sinkers and has surprisingly little armside run.