Thank you for your post. I thought I would address some of the ‘hogere wiskunde‘.
You are correct, I do manually add the emojis for each post. Personally, I think it helps to quickly and easily add context. I am sure that I could use shortcodes for this, but have never gotten around to it. If you are interested in this, Aaron Parecki has taken this even further.
I hope that helps. I recommend the IndieWeb Chat if you have more questions.