Representation in anime is more than just the american progressive ideal of "representation" usually meaning "where's the PoC" though this list will have a good few pieces with PoC representation. Also expect an over-representation of Shinichiro Watanabe. Also i'm counting manga.

There will also be a fair bit of LGBT anime/manga here because I am LGBT and like LGBT anime/manga. Also also this isn't saying that anime doesn't have a representation problem, because it does, just that there is a wealth of series that will give you what you want out there.

Also Also, read this post by @_JackPBrown about many of the shortcomings of Japanese media with regards to Black representation in media https://www.jacksonpbrown.com/anime-and-manga/2018/8/2/thoughts-on-the-promised-neverland-and-black-women-in-manga

Carole and Tuesday is Shinichiro Watanabe's most recent series, chock-full of representation from every side, alongside an explicit antiracist message.

Cowboy Bebop speaks for itself. Intentionally multiracial by design.

Golden Kamuy puts the oft-shunned Ainu people of Hokkaido front and center, exposing people to a culture that had been suppressed by the Japanese government for a long time.

Ping Pong the Animation has Kong Wenge, a Chinese nationalist living in Japan

Keep Your Hands Off Eizouken! has multiple reoccurring black characters that are important to the plot and are great!

one of the hero factions in Code Geass is Chinese, alongside a pretty multiracial class with an antiracist message.

There's this fucking series

Of course I have to mention Bleach

Revolutionary Girl Utena has both LGBT rep and Anthy, a character integral to the plot

Sarazanmai is an anime ostensibly all about a gay relationship!

Promare is absolutely gay fight me and takes place in a multiracial city and has an antiracist message to boot.

Yuri on Ice has a VAST multiracial cast and lgbt themes!

Sailor Moon has a gay couple and a lesbian couple that are both treated seriously!!

The works of Kabi Nagata are all about LGBT+ identity, especially her work "My Lesbian Experience with Loneliness"

Shimanami Tasogare is another manga all about LGBT identity.

Osamu Tezuka is oft-cited as a leftist creator, his works tackling gender, race, and everything else under the sun, so we'll be going through a couple of his manga next. Note that what may seem a little quaint now was a bit more progressive at the time - and Tezuka knew that

Note that Tezuka was not always as progressive as he was, a lot of his earlier works are plagued by racism similar to that of Walt Disney's cartoons, but he, unlike Disney, improved and learned.

Princess Knight is about a Princess who, before God made her, was given the heart of both a girl and a boy. Tackles trans identity questions before a lot of other japanese media about trans identity.

Message to Adolf has a Jewish lead, and is heavily antiracist

Wandering son is about the trans identity as a middle-schooler. I haven't read all of it but what I did read was heartwarming.

Many people love Canary from Hunter x Hunter! A more popular pick but still.

I have literally run out of space on this thread but this is just a toe-dip into diverse anime. It exists, it's just not going to be found by looking at the Crunchyroll "Currently Airing!" tab a VAST majority of the time.