First step following this article, this LoRA is an extract of CuteIXL
It is based on WAI-Illus (V13) but should be able to be used on other Illustrious checkpoints. It can be considered as an evolution of NJ Vector Style, and can be used as-is or with the same trigger words for a more flat effect (so, "Flatline, Flat vector illustration, Black outline, Vivid colors")
Since it is a UNET only LoRA, it will follow prompt more closely than the full checkpoint, so less surprise details, more predictible but maybe less fun.
Here is a comparaison of this LoRA effect versus NJ Vector Style and no LoRA at all:
