Here are several swatches of MAC eyeshadows from the green family (mostly permanent shades) that are now part of The Swatch Gallery.
Newly Minted is a green-based teal with a matte finish. It had a Matte2 finish, but it was discontinued. Make Up For Ever #93 comes the closest–it’s a little brighter but has better color payoff.
Shimmermoss is a blue-teal with a silvery sheen. It has a veluxe pearl finish. Milani Teal the Truth is similar in color but a touch darker, while
Aquadisiac is a green-tinged aqua blue with a soft sheen. It has a lustre finish. Make Up For Ever #168 is the only dupe I could think of, but it’s much darker and not so much an aqua.
Aqua is a soft aqua blue with a matte finish. It’s a little powdery and can look chalky on some complexions. Milani Caribbean Sea is similar in color, though a little darker and shimmery. Inglot #345 has a similar lightness but leans greener.
Plumage is a blackened blue with just a hint of green. It has a matte finish. Inglot #340 is not quite as dark, but it is very similar in color and more pigmented.
Prussian is a dark navy blue with a Matte2 finish. It has been discontinued. Make Up For Ever #60 is the closest shade I could think of, but it is much darker and not quite as blue.
Deep Truth is a dark blue with a frost finish. This is a shade with a fair amount of dupes/cousins. Just to name a few: Make Up For Ever #308, Milani Blue My Mind, and Inglot #428.
Freshwater is a bright, medium blue with a veluxe pearl finish. Inglot #426 is similar, a little darker. Make Up For Ever #167 is also similar but a bit darker.
Blue Calm is a brightened, medium blue with a veluxe pearl finish. It is a PRO shade. It’s just a smidgen lighter than Freshwater (and thus is a smidgen lighter than the comparables listed for Freshwater).
Electric Eel is a bright but darkened cyan blue with a satin finish. Inglot #371 is very similar. Urban Decay Electric is slightly less blue. Make Up For Ever #72 is darker.
Sky Blue is a pale, pastel blue with a white sheen. It has a frost finish and was a PRO shade but is no longer available. Make Up For Ever #150 is very similar. Cle de Peau #112 is also similar but a little lighter.
Winkle is a cornflower blue, almost periwinkle, with a satin finish. It is similar to Inglot #369.
Moon’s Reflection is a purple-tinged blue with a silvery-white sheen. It has a veluxe pearl finish. The closest color I could think of was Inglot #429, which leans more on the purple side and has a brighter white sheen.
Atlantic Blue is a deep, intense cobalt blue with a hint of indigo. It has a matte finish and is a PRO shade. Make Up For Ever #159 is similar but has less violet in it, while Inglot #388 is a little darker and has less blue.
MAC’s matte eyeshadows have a drier texture, and they often perform better in actual application than merely swatched on the arm. Shades like Aqua, Plumage, and Prussian don’t always swatch perfectly but Plumage and Prussian work better when applied. Aqua is a finicky shade that sometimes works but not consistently, and the product itself seems to be inconsistent–some pans are better than others.
Atlantic Blue is one of the best matte shades by MAC, because it’s so intense. Shades like Deep Truth, Freshwater, and Electric Eel are classic blues–all three lovely in color payoff and texture. Electric Eel has all the hallmarks of a matte but it has a satin finish, so it’s easier to work with. Sky Blue can be tricky to work with, similar to Aqua’s issues.