So is it ok for Morgana to 1-shot adcs when she hits 6?

Lolol morg doesn't one shot ANYONE at level 6, especially without damage items. You were either already low or there were 2 people.

Wait...what...

I have never in my life seen a Morg one shot an adc. She can't, she doesn't do that much damage especially with no damage items. Unless there is a glitch, 1 ability from her will not one shot a completely healthy adc. If you are already low, she can kill you...but that isn't one shotting if you aren't at full health..