My guess, if they do nerf Mei, it’s probably going to be less Slow effect on her primary fire.
Like 20% Initial Slow, instead of 30% Initial Slow.
Or a tiny bit less Freeze, such that the double icicle isn’t possible.
Like 1.3sec Freeze, instead of 1.5sec Freeze.
That said, if you listen to any Pros, Mei is gonna be good, but it’s Hanzo that gives the damage and shieldbreak that makes that pairing work.
I figure neuter Hanzo’s shieldbreak, and you’re get both less Mei from Hanzo/Mei, but also less Mei from Reaper/Mei.