I find that tools like Mermaid are pretty invaluable, especially when editing very large processes. Draw.io diagrams tend to get pretty unwieldy as they scale and editing inter process stuff if you forgot something quite frustrating.
Sequence diagrams are possibly my favorite feature in Mermaid: https://jessems.com/posts/2023-07-22-the-unreasonable-effect...
Admittedly I primarily use D2 nowadays. The only features I miss in D2 from mermaid are the GitHub automatic rendering and Sequence diagram numbers. https://play.d2lang.com