I’m in the mood for a headcanon, and it’s that Nathaniel gets a sparrow Miraculous.
The superhero Sparrow was made for the Quantic Kids concept, but he was dropped, with Kid Mime replacing him, and eventually, the entire concept he originated from dropped. However, since Miraculouses are based off of animals, it would be a missed opportunity not to bring back this superhero as a Miraculous holder. His design is marvelous, and it even if it’s tweaked in any sort of fashion, it would still look fantastic. His concept art also shows him as being stealthy, a different kind of way to be a superhero than the usually open and upfront Ladybug and Cat Noir. He could be handy in watching for anything notable, a spy that isn’t cunning and deceiving like the Fox Miraculous holder, and protecting anyone in need of help.
Sparrows represent inclusion, creativity, vigilance, self-worth, and productivity. I can see some of these virtues being things that Nathaniel is good at, like creativity, or things he can work on, like his feelings of self-worth. If going by the color theme theory, there isn’t much to Nathaniel’s appearance that is similar to a sparrow’s appearance, but personality-wise, he doesn’t often speak out or draw attention to himself, preferring to be an observer than having to get greatly involved in a situation. As a superhero, Nathaniel could learn to work with a team, but he could be fine going on solo missions and being by himself. He would also have creative ideas to offer, being a creator of superhero comics and always thinking of multiple possibilities.
I have no idea if Nathaniel will ever get a Miraculous in the show at the moment, but I like the idea of a sparrow being a potential Miraculous match-up for him.