@Simon Android. Maybe it’s different on the different platforms. On Android I have not noticed the features which @y-ZZ-a says are already present in the app (search emoji by name and see the emoji description).
I was actually going to use one of the ascii art emojis recently, couldn’t find it, then remembered it was on a different platform where I saw it offered. It can be especially useful for the more complex emoji art emojis. The basic ones can easily be done manually.