Non-MLB
Although they have not thrown an MLB pitch in 2024, R.J. Alaniz threw 397 pitches that were tracked by the PITCHf/x system between 2018 and 2021, including pitches thrown in the MLB Regular Season and Spring Training. In 2021, they relied primarily on their Fourseam Fastball (93mph), Change (87mph) and Slider (84mph), also mixing in a Sinker (93mph).
In 2021, compared to other RHP:
Their fourseam fastball has heavy sinking action, has an obvious tail, is an extreme flyball pitch compared to other pitchers' fourseamers and has essentially average velo. Their change (take this with a grain of salt because they've only thrown 17 of them in 2021) dives down out of the zone, is slightly firmer than usual and has slight armside fade. Their slider (take this with a grain of salt because they've only thrown 16 of them in 2021) is basically never swung at and missed compared to other pitchers' sliders, has exceptional depth, is an extreme flyball pitch compared to other pitchers' sliders and has short glove-side cut. Their sinker (take this with a grain of salt because they've only thrown 13 of them in 2021) generates an extremely high number of swings & misses compared to other pitchers' sinkers, has an obvious tail, is an extreme flyball pitch compared to other pitchers' sinkers, has slightly above average velo and has some natural sinking action.