Modeling
According to the background of the story, the character is set as an abstract cute elf. This is a design of the character on land. In this Level, the character is in the water, so there is no clothes.
Rigging with Advanced Skeleston5
Animating with HumanIK
I used the swimming action from the Unreal Official Store for the character animation. Use HuanmIK to quickly get a basic swimming animation. However, there will be many mistakes in such animation, which needs us to adjust manually. Parts of the skeleton can be quickly modified using the Animation Layer.
The above is all the actions of the character. These actions include surface, underwater, fast swimming and slow swimming.