>>536415156
That's because CotW is unbalanced trash and that lack of balance is strongly against Mai in that game, and kind of against Terry to some degree.
Also, SNK dropped the ball on the art style and to further add insult to injury, you can't even choose Mai's classic outfit in that game.

Meanwhile Capcom gave her 3 playable costumes in SF6 already, with a fourth outfit on the character select screen, plus making her look like a sex goddess.
Capcom gave Mai more brand new designs than SNK has in the past 28 years.