bWAR doesn’t have anything to do with K rate or BB rate or hit rate or HR rate. It is strictly run prevention, with adjustments for context. Check out the Player Value — Pitching table. That breaks down bWAR a little bit. They start with the pitcher’s RA9 (like ERA but including unearned runs), then they consider opposition (RA9opp), team defense (RA9def), and park factors (PPFp). So in B-Ref’s estimation, while Scherzer has a higher RA9 than Maeda, overall he has faced better opposing offenses, has a worse team defense behind him, and has pitched more in hitter’s parks than Maeda. Fried too. Maeda’s RA9 is 2.43, and B-Ref calculates that the average pitcher would have a 4.04 against the same offenses, in front of the same defense, and in the same parks (RA9avg). By comparison, Scherzer’s RA9 is higher at 3.40 but the average pitcher would have done much, much worse under his same conditions — RA9avg of 6.12. Similar story for Fried: RA9 of 1.98, vs a RA9avg of 5.85. That’s not to say B-Ref is correct on all of this, but that is the explanation.