I think the biggest trademark of yours has to be the your personification, more specifically the element of yours because i see them around alot. Yours has a unique charm put into it that seperates it from the other personification of the elements. Toying with the concepts of the chemical's group which i find creative! There's not alot of people who does it and i appreciate your research and concepts. Speaking of which, i like how the references to the source material you put into your characters p much makes them as a whole and still making them human with balanced and detailed personality. I mean, i know that's the point of personification lol but yours feel... more human with all the things around em. Their job, personality, role, just ties together nicely to the environment they live in
And can't forget your memorable artstyle. Imo, the colours and media you use is p much somehing i identify you with. I think it's because of the soft colours n shading of a colour pencil, which i dont see quite often? It's such a neat thing to see in traditional media and yours has such a nice texture to it. The way you draw the facial structure is also one of a trademark. I cant describe why it's distinct but something about the stylized shape is unique