I actually found some interesting stats on bref in the "Pitches" category under Pitcher Comparisons...
... for Kimbrel (2010-20), Barnes (2014-20) and Uehara (2009-17).
Strike %: Kimbrel 64.3, Barnes 61.6, Koji 70.9.
1st Pitch Strike %: Kimbrel 59.7, Barnes 57.9, Koji 68.0.
3-0 counts seen: Kimbrel 102, Barnes 61, Koji 38.
0-2 counts seen: Kimbrel 782, Barnes 333, Koji 658.
3-pitch Ks: Kimbrel 203, Barnes 56, Koji 125.
And my favorite:
4-pitch walks: Kimbrel 40, Barnes 22... Koji Uehara 4.
Just for perspective, I looked up Eckerlsy (1975-1998)... 72.1 and 69.7; 3-0: 68; 0-2: 1,013; 3-pitch Ks: 163; 4-pitch walks: 11... in 24 years.