From Engadget[0]:
> The workflow of The Lion King was vastly different to The Jungle Book. MPC worked on 'master scenes' in London with industry-standard tools such as Maya. It then developed an "asset management system" that could translate the scene into something that was compatible with Unity, a popular game engine.
Also, this YouTube video[1] goes over the process in more detail.
[0]: https://www.engadget.com/2019-07-29-lion-king-remake-vfx-mpc...