IAD 6d get you in there. Mu is pretty slow, and as silly as it may sound, she's one of the chars Rach can blatantly get to.
Since zoning is useless, use wind in this match to manuever wisely. backdash 4d, iabd 4d dash 6d, all of these actually get Mu guessing. With Rach moving so freely, Mu might attempt one of her slow ass normals. That's the time to strike.
lt's like 5.5 Mu if l had to guess. Mu might play like Rachel, but this match is more like CT RC vs LI. Watch for 6c, stay out of the corner