Mitsuru should be at advantage after Labrys does 214A/B (the overhead) because she has more range than Labrys.
As WintySoSol, outside of 5AA and 2AA, Labrys isn't really that safe. And Labrys's reversal isn't that great. Bait and punish it if it is causing you that much trouble.
It really sounds like you are getting flustered fighting against Labrys and messing up rather than Labrys being a hard match-up.