A well timed Carnage Sissors will beat her 5D. If she tries to go for anything out of a blocked 5D, you should be able to Carnage Sissors her on reaction for a punish.
Honestly, the best thing I've seen to do in this match-up at the start of the match is stand and wait a second. If she decides to air dash back and do a j.D, it whiffs and you can run in to get your offense going.
I really, strongly disagree with air dashing in the matchup in neutral. Super jumping and clever use of double jumping will work fine. Dashing and barriering on reaction to stuff works really well.
If you think the Lambda is mashing on Calamity Sword, 2C -> block. Since 2C gattlings into both 6B and 6C, people will always think you're trying to go for high low shennanigans.