Jelly style was not the first by MidJourney. It was actually from Yanjun Cheng way long before AI art started. His style is famous on this specific jelly, pastel look, rainbow colour skin.
No one, ever, had done any artwork like Yanjun Cheng style. His artworks are absolutely unique.
Noted that there will never be the AI model can replace the artist. This is merely a scratch on the surface of his work. Please consider buying his prints at https://yjc.artstation.com/
Weight between 0.6 to 0.8 seems good.
His artwork in low res 400x400 attached.
Kohya_ss config: 50 repeats, 2 batch, 2 epoch, net dim, alpha, conv dim, alpha 16,16, 8,1.
No commercial for the model and its products.