I recently made the switch from Windows to macOS and before I always do like copy an image -> quick edit -> paste directly into Slack/Teams. I couldn't find a lightweight app that felt just right without saving files to the desktop first, so I decided to write one myself using SwiftUI.
Ctrl+shift+V to paste the image -> Make the edit -> Cmd+C to copy back to clipboard.
Its super light and free, I hope it helps your productivity as much as it helped mine
