The animations were never done in the traditional way, it's not summertime saga. The oldest animations have always been made with Live2D, and the most recent with Spine.
Godot has a Spine plugin that lets you use the game engine to display animations, instead of the archaic system of simply having in-game video files that take up far too much space.
If the game exceeds 2GB, it's no longer possible to offer an Android version, so switching to spine and having the rendering done by the game engine is a must.