Zulip is the best chat application, from a “design” perspective at least, but slack has huddles and works really well and is pretty standardized. Screen sharing with slack is amazing as you can draw on your coworkers screen without them needing to enable anything. Discord has the best long term voice calls, but is really weird for messages. And screen sharing isn’t as nice for work stuff but is great for video games.
it says it’s a Notion alternative… Not a Google Docs alternative.
One Notion FOSS alternative I’ve been testing out is SiYuan.