Yes on the effetre Sage green. Slytherin is almost black and there isn't a transparent green that dark, unless there is a lauscha or other that I don't know about.
Slytherin, you'll see a comparison with Sage green
https://www.creationismessy.com/color.aspx?id=68
Eel Grass is a lighter version of slytherin
https://www.creationismessy.com/color.aspx?id=389
Algea was the closest, but also sold out, this is why I hate limiteds!
https://www.creationismessy.com/color.aspx?id=69