Otomo's 1991 Roujin-Z was made available for viewing on YouTube this past year. It's 1h20m. Link: https://youtu.be/itg4zKaUMgY
There's also Otomo's 1995 Memories. It's great. I haven't found a good version of it on YouTube, but a quality stream of it is available on Amazon Prime.
Otomo also worked on Metropolis (2001) and Steamboy (2004). They're both great.
I wouldn't call it a great anime in general, but for our niche, it can be amusing.
- Death March to the Parallel World Rhapsody
- That Time I Got Reincarnated as A Slime
- The Dungeon of Black Company
- No Game No Life
- Outbreak Company
- Log Horizon (in a computer game, but has a lot of worldbuilding)
- Overlord
- Re;Creators
- Arifureta: From Commonplace to The World's Strongest
- In Another World with a Smartphone (generally considered so bad it's good)
- The Wise Man's Grandchild
- The Saga of Tanya the Evil
I'm guessing you might like the following:
- Sword Art Online
- .hack series (the anime chronology begins with .hack//sign)
If you want something a little bit more tech related with less fantasy:
- The Irregular At Magic High School
- Ghost in the Shell: Stand Alone Complex
- Stein's Gate
- Serial Experiments Lain
- Bubblegum Crisis
- Outlaw Star
- Big O
- Code Geass
Just a personal recommendation:
- Spice and Wolf
Secondly, I've watched many of these shows myself, so when you mentioned Knights and Magic (which I enjoyed when it came out in 2017), I knew the kind of premise you were looking for; Coder/office worker/intelligent & talented student uses his knowledge of the laws of nature of his previous world to become overpowered in the new one.
I can't define it, but I feel like there is a link between the animators who worked on Ninja Scroll and the ones who worked on Puppet Princess (2000). Puppet Princess is short but looks like a lot of work went into it for it's time. If you want to see that, the only streaming service I could find with it was VUDU.
now i have a few favorites that i always rewatch: - hunter x hunter; the greed island arc was my favorite - the irregular at magic high school: magicians are ranked in the school by their compute power and speed, but the protagonist basically has orders of magnitude of more RAM than everybody else