you need to draw your own things for those levels of abstraction on wiring chart, its basically like being a cartoonist at this point without clear standards or guidelines. you need to draw them as you think your audience wants to see them.
This is what I see
1) lazy/strict documentation : normal industrial wiring diagram is shown (as in a motor and a drive) with footnotes about what connectors are appropriate (send to the most advanced users). This feels like getting a balonga sandwich. Yea whatever dude, take your gruel and go.
2) more creative/thoughtful documentation : some kind of clear caricature is drawn of the connector to be used. (has more mass market appeal). Usually the advanced users won't complain because its a sight for sore eyes to see someone draw anything but a dot and hit a typewriter. I prefer this kind. Also since you see it on the paper you are WAY less likely to get a support question or have people mess it up (its hard to fuck up copying a picture). This is kinda fancy and more nutritious.
If someone tried to define a international or even national symbol for a wiring nut, the confusion would be hilarious.