A nice 3D MMO is being developed and the creator is putting their test-phase releases here on itch.
https://lartu.itch.io/eterspire3
I feel like this cool project deserves more attention. It is a big fat blob of potential. There is currently very little to do in it, you can only run around and kill monsters and sell loot to an NPC, and there is no player interaction features except a chatbox, but it seems to be otherwise off to a decent start and I think the creator, Lartu, can take it a long way if they get more support and feedback. It'd be great to see more players jump in and help give their system some proper testing. There are already a couple regulars, but it mostly stays a ghost town and imo it deserves better.
Account creation is all handled by an in-game form, no need to a website for it. One thing I will caution you on is that connecting to the server when you log in takes a while. You're going to think it isn't working but it only takes a minute. So wait a bit before you give up and close it. Nevermind, that problem seems to be specific to me. You will probably connect just fine.