Ring4 Meeting - Dead simple video conferencing - free, in browser
MEE6 - MEE6 is a multipurpose Discord bot with moderation capabilities, leveling, Twitch alerts, and an easy-to-use online dashboard.
Stork.ai - AI-Based Collaboration for Hybrid Teams. Rich media messaging, advanced video and voice conferencing, auto-transcribing and screen sharing. Serendipitous meetings at the water-cooler with your human and AI teammates.
YAGPDB - YAGPDB (Yet Another General Purpose Discord Bot) is an advanced configurable Discord bot providing a load of features for help with managing a server.
openmeet - Account free video conferencing with a rooms component that lets you use VC within a physical meeting room. The server can also be hosted in your own cloud for extra privacy/security.
Arcane - Leveling, XP, ranks, voice, role rewards, auto mod, reaction roles, custom commands, YouTube alerts.