1. Costa Ronin
This tall slice of Russian goodness nabbed his first major role on the equally underrated series The Americans, where he played Oleg Burov, a KGB officer. He also starred in the last two seasons of Homeland as Yevgeny Gromov, again playing a Russian spy. Ronin is particularly skilled at leaning into his natural charm on-screen and knowing how to underplay it when he needs to be subtle, or overplay it when he needs to be smarmy. Unfortunately, despite his perfect English (he learned the language after moving from the Soviet Union to New Zealand and then Australia), his strong Russian accent means that Hollywood will probably continue casting him as a Russian agent or East Berlin Prison Guard #2. Here's hoping that that he'll score another excellent series like the Americans, or at least score some good roles in foreign film.
2. Annet Mahendru
Another Americans alum, Mahendru actually spent a large chunk of her screen time opposite her co-star Ronin, and she gained much acclaim for her role as the troubled double agent Nina Krilova. The biracial actress also has an interesting background: she was born in Kabul, Afghanistan, to a Russian mother and Indian father. She is fluent in 3 languages (German, Russian and English) and can also speak Hindi, French and Persian. Since The Americans ended, she has nabbed a few film roles, guest-starred in the 2016 X-Files along with a few other TV series and is set to play a lead role in yet another Walking Dead spin-off, The Walking Dead: World Beyond. This makes OP mad because Mahendru is way too good to be starring in that trash, but get money I guess. Let's hope we'll see her some bigger projects in the near future!
3. Sophie Cookson
Cookson bears a striking physical resemblance to Alyssa Milano, but thankfully, that's where the comparison begins and ends. After a few side roles in films such as Kingsman and The Huntsman, she went on to play the lead in Red Joan as a British asset for the Soviet Union, who supplies the Russians with nuclear secrets in an effort to maintain peace in post-WWII. Recently, she also played in the lead in the BBC series The Trial of Christian Keeler (based on a true story), and has also starred in the Steve Coogan-led film Greed. Her next role is in the sci-fi film Infinite, and she will be starring alongside the likes of Chiwetel Ejiofor and Rupert Friend.
4. Hong Chau
It's possible that Chau's most prominent role to date was on HBO's Watchmen, where she played the antagonist Lady Trieu. Before that, she had appeared in movies such as Inherent Vice and Downsizing, as well as nabbing a voice role on Bojack Horseman and appearing on Big Little Lies. Chau comes from humble roots: her parents fled from Vietnam in the late 1970s and lived in a refugee camp in Thailand, where their daughter was born. She grew up speaking Vietnamese as her first language, and learned English at school. Her next role will be in Artemis Fowl, where she will play a fairy. Let's hope we'll see her in some more excellent stuff very soon.
5. Ashton Sanders
Sanders can currently be seen in Netflix's new movie All Day and a Night, where he plays an inmate named Jakhor who ends up landing in the same prison as his father. Sanders' breakout role was in the award-winning and groundbreaking Moonlight in 2016, where he played the teenaged version of the main character, Chiron. Since then, he has starred in movies such as HBO's film Native Son and sci-fi movie Captive State. For his role in All Day and a Night, Sanders has received rave reviews, with some critics already calling it one of the best performances of 2020. Fans are (rightfully so) clamouring for Sanders to continue nabbing bigger and better projects - let's hope that we'll get our wish sooner later than never!
Source: me, my bike, and the amount of free time quarantine has granted me
PLEASE feel free to add anyone I've missed in the comments, it's a very short list!