Emacs with crdt.el, or neovim with instant.nvim are both open source and free implementations of collaborative editing with crdt's. Its going to be a bit of a struggle getting your coworkers to use emacs/neovim though
a combination of "there is no standard", "selling collaboration to businesses is way to make money", and that how editors handle files changes from editor to editor, so its a bit hard to sync
- zed.dev has crdt's/collaborative editing as one of its selling points, but they're planning to offer this collaboration as part a paid service to businesses.
- vscode has its own sycronous collaboration plugin, but its proprietary and they declined to release the source code or offer to port it to other editors
- you could probably build a plugin that bridges emacs and neovim, but it might be a bit slow as you'd have to "translate" the buffer from one editor to the other
There is an inherent difficulty in implementing it, getting asycronous collaborative editing right is hard. Combine that with how few people on emacs/neovim actually use collaborative editing (emacs still has a mailing list and does code via patches) and the chance for a "universal" version is practically nil.
Is there some inherent difficulty is this, or is it just "there is no standard" -> "nobody implements one"?