The Leader. It is the indisputably most communist anime ever made. https://vid.puffyan.us/channel/UCJDHpjhmJlbNFPBEheFhypQ (I don't think this is all of it)
Shen Sekai Yori (from the new world) A bit of a streach but it has surreal worldbuilding with psychic powers but the "villain" is pretty much a Marxist in how he resolves his people's problems. It shows very much the third worldist position. https://www.crunchyroll.com/series/GR2P51V8R/shin-sekai-yori-from-the-new-world
Moriarity the Patriot. It shows what happens if you try to just kill all of the bad nobles without actually forming a mass movement. You need a mass movement. A fun inversion of the Sherlock Holmes stories. Its like Deathnote but without magic and Light Yagami detests the nobles alot more than petty criminals. https://www.crunchyroll.com/series/GXJHM379D/moriarty-the-patriot
Shadows house. Another anime that is about organizing in the imperial core but obstructed through some very wierd magic systems. Manga was better. https://www.crunchyroll.com/series/G1XHJVEXE/shadows-house
Promised Neverland (not season 2). Same as Shadows house, but a different magic system. https://www.crunchyroll.com/series/GYVD2K1WY/the-promised-neverland
Not sure if communist itself, but Miyazaki's Princess Mononoke have a strong environmentalists and anti imperialist message.
Miyazaki was a communist until the fall of the USSR. And while he ditched ML like a lot of people unfortunately did in that post-soviet period, he's since said a handful of times that he still considers himself a socialist, generally.
So, looking at most of his movies, they're stuffed full of leftist themes.
Kiki's Delivery Service is very much about Alienation under Capitalism. Kiki's hard work ends up burning her out and straininh her relationships with others, because she's commodified a thing she loves: flying, in order to survive. And the movie contrasts that with the lesbian forest painter Lady who works hard on her art, on her own terms, unburdened by the whims of capital.
Spirited away has too many themes to count, but let's look at the design of the bath house. It's mostly a Meji-era architectural style, but when Chihiro goes up to ask for a job from the witch who owns it, the architecture is suddenly very European. So visually, we're being told that the west is literally lording over, and owns, Japan.
And a persistent theme is also the ways Japan is disconnected from its culture. Chihiro doesn't recognize the spirit shrines, unceremoniously dumped by the roadside at the beginning of the film. And characters say of the train that it "used to go both ways, but now only goes one way". The train is death. Spirits can only go further into the spirit realm, and never back to visit earth.
And put together, the film is pointing to Japan's disconnect from its own history and culture due to US imperialism.
Miyazaki is really interesting to examine when you consider his history with socialism: he exemplifies Japan's left as they became disillusioned with communism. He doesn't speak to ideology directly but the way he grapples with development, imperialism and egalitarianism is nuanced and always changing.
Mobile Suit Gundam: The Witch from Mercury has some anti capitalist and anti imperialist messages and its pretty good.
