My favorites are Darlene and Angela. I agree about Streep's daughter.
I personally find Rami's performance great but Slater definetely doesn't deserve those nominations.

Which female actresses are your favorites? Meryl Streep's daughter stood out to me as maybe the least convincing acting on the show. Angela stands there blank-face in most of her scenes. Darlene's character could maybe get a nod though. Joanna Tyrell doesn't show much emotion in her scenes.
Malek's performance is decent but I found Slater's acting in the series to be terrible.

Rami is great. Slater is good but I don't think he deserves those nominations more than the female actresses on the show.

Malek is great on this show. He seems to be the most talented actor. I'm not sure why Slater is getting praise for what he does

I've seen Rami in a few movies and I don't think he's a particular great actor the role he plays on Mr Robot doesn't exactly involve much effort.
Slater has always been great I think. I thought he stopped acting for a few years, but I checked his page and it just turns out he's been in really really bad movies that most probably haven't heard of, or knew to avoid.

The only thing I can think of is that they cancel each other out in the supporting category, or split in categories, while Malik and Slater are clearly defined lead/supporting, and also don't compete with each other for a nomination.
I think these two factors make it harder for one of them to snag a nomination even though the women are so compelling.

The girls could stand some awards as well, but I feel that comments like "Malek's story line was secondary, he was more the supporting character" is a large overstatement and misrepresentation.
They did get one episode without Elliot though.
Brevity is the soul of wit.