Unity - The multiplatform game creation tools for everyone.
Animaze by FaceRig - Livestream or Video Chat with custom 2d & 3d animated avatars. Add backgrounds & props with the Animaze editor. Use on Twitch, Discord, Skype, Zoom, & more
Godot Engine - Feature-packed 2D and 3D open source game engine.
VUP - VTuber Maker & Animation & MMD/Live2D facial capture software.
Blender - Blender is the open source, cross platform suite of tools for 3D creation.
Mug Life - Create 3D characters from any photo.