Attention
This is not a ready-made solution, but actually a concept! (Written quickly and very crooked. USE AT YOUR OWN RISK. Make backups of your characters before use)
1 Run through the menu 3ds max Script -> run script.
2 Import the model via import rather than drag and drop
3 Auto rotate bones does not work with all meshes. The net should be roughly similar to the Mannequen.
(conceptually it works like this: has a cycle unlink all bones rotates in accordance with the position of the bones Mannequen-> links back).
Easy retarget
Auto Rotate Bone
Download:
ER+AR
Easy Retarget
Auto Rotate Bone