Epic has a plan for making Animation & Rigging Toolkit for 3ds Max?

Incorrect!
Biped in 3ds max isn’t buggy at all, it’s the industry standard for animation in almost every AAA game developer in the world. It’s only buggy if you don’t know what you’re doing :smiley:
CAT is buggy and awful, which is why no one uses it and Autodesk will dump it soon.