Excalidraw is nice. Also, I want to throw in a mention for mermaid.live (mermaid js). A little less flexiblity but it’s nice. There’s also kroki.io which hosts a lot of these types of apps.
Have you tried the Excalidraw plugin for obsidian? This may be closer to what you’re looking for. Otherwise, would the canvas feature do what you need?
Excalidraw is nice. Also, I want to throw in a mention for mermaid.live (mermaid js). A little less flexiblity but it’s nice. There’s also kroki.io which hosts a lot of these types of apps.