I'm not personally picky about flowcharts because I'm not involved in any of the fields where they are used professionally, with formal conventions. Anything that has arrows, color coding, and shape coding, that are easily intuited from looking at the diagram or easily explained with a visual key, is fine with me.
I gave an example of my personal comic style above. Panel One and Panel Two are collections of professional comic scripts, so they are a good place to look at examples of the different styles pros are using. The style used depends a lot on whether the writer can supply crude drawings (more like a storyboard than a plain script), whether the artist likes a lot of stage directions or likes to be left to their own devices, and whether the script has to be sold to an editor or evaluated by a committee, or whether it is being given directly to an artist, or even whether a writer/artist is creating it for their own guidance before starting to draw.