Per a comment I posted, "impartial but left [or any other] take" is a bit of an oxymoron. Still, if you're unapologically left leaning and concerned with "rights of all citizens, fairness, green issues, public social services, equality etc." you might find this answer interesting.
If you like the Guardian's coverage, The Independent is a relatively decent UK news source as well. There's an assumed pro-Russian bias because of its Russian oligarch owner, but having read it for a few years it felt a lot less obvious than the bias on RT, if present at all.
If you read French, Le Monde is fairly balanced too, with a left leaning tint -- definitely not as strong as Libération or Charlie Hebdo, but there nonetheless. If you can be bothered to buy an actual newspaper, look into the Canard Enchaîné, a weekly satirical that as of writing this still doesn't offer any online version of its paper. They're something of a best of breed that does no ads and are entirely self-funded, yet still pulls off breaking a laundry list of stories and doing investigative journalism. Marianne is a magazine that strives to be similarly independent, and is more strongly leaning left. Mediapart is also worth a mention as an independent outfit with a focus on investigative journalism, and offers a selection of English language articles.
In German, I've yet to come across anything that got me hooked. DW has some English articles and fairly good documentaries from time to time. For the rest, it's basically a barrage of "turn your ad blocker off" that I can't be bothered with for security reasons, and a surprising one at that given how savvy Germans seem to be on the topic. There probably are a few good sources that I missed, but my research on German language press led me to think it's digging itself into a hole.
In English, you'll need to cross the pond and/or explore other mediums to get more coverage. NYT and WP are left leaning classics. The WSJ is a classic too if you don't mind the center-right wing bias. Democracy Now and The Intercept are worth a mention if you don't mind unapologetically left leaning outfits. Vox is bigger than the latter two, and has some interesting articles and videos from time to time. Where they shine is on podcasting -- with the notable exception of their foreign policy podcast, Wordly, which is so offensively misleading on such a regular basis that you're basically better off not listening to it at all. If you like Podcasts, also check out Crooked Media, which is heavily into foreign policy, albeit from a US and heavily left leaning viewpoint. And by all means check out Chris Hayes' WITHPod podcast, which has the best primer on Brexit I've come across in the past 2-3 years and otherwise has spot-on (in my humble left leaning opinion) takes on a wide range of other topics.
Aside: You tagged this with fake-news. I've no idea what you're getting at there, but there's a difference between two people having different opinions on a fact (government spending on this or that is a good or bad idea before the data is in) and two people having their own facts (earth is round vs earth is flat). The first is about debate; the second clearly is not, and is what fake news is about.