I haven't been able to make sense of how to add character models so I will leave this link here for the tech-savvy-ish people. I got the guide for importing via unity roughly translated so it should be kinda understandable for anyone who wanted it in English with not much effort:

https://www.dropbox.com/scl/fi/a7b029eagpi5eqitadh4s/KumaKuma-unity-guide-EN-1.docx?dl=0&rlkey=4kqo3zs3hzggiw51dkvua7m2m

Also, I don't really understand it that well even in Engrish, but the first couple of images seemed to have been doing something in Autodesk 3DS MAX 2015 Edition then the rest was done in unity version 5.6.3 specifically. Maybe it's a hella easy process just not explained very well. If that is the case whoever gets this done, please create a Youtube video for us plebs.