What’s the difference in my Elekids?

So I have a handful of Elekids and one of them says I’ve never evolved one like that before. But the other Elekids all recognize evolutions. (I have all evolutions.)

It’s not shiny or lucky or an event Pokémon. I can’t figure out how the Elekid in the first shot is any different than the Elekid in the second shot. Please help.