For teams I've used Raneto[0] in the past.

I use Notable[1] and MkDocs[2] for personal notes and technical documentation respectively.

All three are markdown powered of course. Raneto and MkDocs can use a Git repo with your preferred build pipeline and the HTML can be hosted internally or on Netlify, etc. Works well for teams.

With Notable I use Syncthing to keep notes synced, but that's a personal use case.

For teams you may also want to give Outline[3] a try. I haven't used it as yet but it does looks pretty good.

[0] https://github.com/gilbitron/Raneto

[1] https://notable.md

[2] https://github.com/mkdocs/mkdocs

[3] https://github.com/outline/outline