>>63396385I might be somewhat informed in this (don't ask) - art takes a while, because an artist needs to layer everything in a non-conventional manner. Usually artists do lineart, flat colors and shading, but in live2d you need to split everything. Hands, fingers, front hair bangs, head, nose, eyelashes, sclera, iris, middle hair bangs, back hair, if you have any accesories, it's good to split them too. Then you send that to a rigger and they work their way around it. If the rigger is good, they'll contact the artist in case there's some fixes necessary (for example, the layering of neck didn't give the rigger enough space to move the head), sometimes the rigger fixes those on their own. Sometimes, if they're a bad rigger, they just say "fuck it" and deliver Gura.
Either way, about the time:
Art might take 2-6 weeks. If you need a character sheet and a full design from scratch, then you go back and forth with the artist several times. If you already have a design and just need an update, or a new style (like ironmouse), then it probably would take less time.
Rigging takes a lot of time if it needs to be done well.
https://twitter.com/__himey/status/1302233959544233984 an example of layering
https://www.youtube.com/watch?v=3kU8iqMt1KM an example of one of the best rigging in the industry.