What’s the best non-vim vim mode editor?

It's already been said, but, Emacs. Ironically. Evil is crazy good (that's an interested juxtaposition). Doom Emacs glues lots of Emacs plugins and functionality extensions together cohesively to create quite an intuitive Vim-like experience.

Emacs with evil-mode is a pretty good Vim, with the added benefit of the whole Emacs ecosystem.

Neovim [1].

Emacs with evil-mode work pretty well (IMO the best "vi-emulation" within other editors; the vi-plugin in JetBrains-IDEs works also quite well, though), however I learned painfully that you need to know two languages in order to configure it to your needs: Emacs lisp as well as well as vimscript for your vim-configuration. And that is just too heavy for me, so I'm back to Neovim.

There was the very promising OniVim 2 [2], which is very fast and powerful. However fundings were not enough, so the work on it came to a hold.

And then there exists a handful of other modal editors with vim-like modes. Kakoune [3] comes to my mind here, which may be currently the most vim-like non-vim editor actively developed (IMO).

[1] https://neovim.io/

[2] https://v2.onivim.io/

[3] http://kakoune.org/

Edit: typos.

I’ve recently started moving over to https://helix-editor.com after using neovim as my main editor for a few years, and despite being more like kakoune than vim (first comes selection, than the action), it’s been relatively intuitive and more pleasant to use in default configuration even than fully customized (neo)vim. I recommend anyone who has the time to try that editing model.

I like spacevim[0] and the vim plugin for VSCode.

[0] https://spacevim.org/

Maybe not the best, but it’s worth pointing out that obsidian (the knowledge base/note editor) has a vim mode.

https://jamierubin.net/2021/03/23/obsidian-and-vim-mode/

I don't know a good one, I honestly just use vim.

I will say that the vim mode in Geany leaves a bit to be desired, but otherwise it's what I use if I want something closer to an IDE

emacs :^)