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 has much less armside movement than typical, has essentially average velo and results in somewhat more flyballs compared to other pitchers' fourseamers. Their slider is basically never swung at and missed compared to other pitchers' sliders, has short glove-side cut and has less than expected depth. Their curve has below average velo, has a sharp downward bite and results in somewhat more groundballs compared to other pitchers' curves. Their change (take this with a grain of salt because they've only thrown 14 of them in 2019) is basically never swung at and missed compared to other pitchers' changeups, has surprising cut action and is an extreme flyball pitch compared to other pitchers' changeups. Their sinker (take this with a grain of salt because they've only thrown 16 of them in 2019) 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.