Have you considered PlantUML[0]? There's plenty of examples on planttext[1].
It's my go-to tool whenever I need to document something visually, whenever I have a meeting with my peers and I want to get them quickly up to speed with the process I have in mind, I just create a quick sequence diagram and we can hit the ground running.
I've been using a product Websequencediagrams, to create the sequence pictures. There is issues around the licensing, and the company wants to sell a a service. I'm in a lab well behind secure firewalls, so a non starter.
There is also the desire to have documents have more types of pictures/ drawings. A Swiss Army knife of drawing tools. In our case it's ok if some of the styles are not as powerful.
It's my go-to tool whenever I need to document something visually, whenever I have a meeting with my peers and I want to get them quickly up to speed with the process I have in mind, I just create a quick sequence diagram and we can hit the ground running.
[0] https://plantuml.com/state-diagram [1] https://www.planttext.com/