Or :sitelen-kijetesantakalu: if other sitelen pona characters are added as a set. It’s probably not a good idea to add all the sitelen pona characters as emojis, probably, but Wiktionary does have vectors of all the characters, and it’s pretty trivial to recolor these vectors white with a thick black stroke such that they show well on both light and dark themes.

Edit: Of course, another solution to making it look good in any theme is to just color it red or pastel green or something, or to put the whole character in a box with rounded edges or something like that, I dunno. Point is that encoding sitelen pona as emojis is a monster task.