Which app produces characters with AI?

I didn't know exactly how to phrase the question, so I'll explain it again now, very briefly: this question is only for those who support AI and not for the AI ​​haters

I have the following problem, I found this video with the Sonic characters

https://youtube.com/shorts/7s1YP0lV22E?si=nGC2WRjddKArnkGr

This showed me that I can also create characters with AI, however I have tried so many AI video programs, but I always ended up with some junk that was created when I used the character names, which didn't produce what I actually wanted, but in this video this guy gets what he wanted, he wrote the app he uses in the video description, I have also googled, but every time I only get image editing (Ai) app and no video editing (Ai) apps

But I would love to make my own website with the Sonic characters, even if it is AI

And this AI is perfect for me..

Now my question: Do you know of an app that can do this, or am I doing something wrong? Do I perhaps need to describe the characters properly instead of just writing their names?

Or are these perhaps just pictures that were made animated with a video AI app?