ART usage without retargeting

Hi.
We are developing RPG game and we have a lot of characters. The issue is that we need to rig them in the way that the characters skeletons must match Standard skeleton (Epic skeleton) so that we can easily use some animations and other cool stuff from UE4 marketplace.

Problem is that moving bones is Maya results in broken animations (i.e. hands go inside body and stuff like that).
As I understand if one wants to use animations from marketplace then he can only rotate skeleton bones in Maya and nothing more?

Or there are some better ways to create custom character rigs and use animations from marketplace without any retargeting at all?

Actually found solution (using Maya) after almost one day!

  1. Export UE4 Mannequin Skeletal mesh as fbx
  2. Open Mannequin in maya
  3. Import your model into the same scene
  4. Fit your model to Mannequin skeleton if needed (DO NOT TOUCH JOINTS)
  5. Substitute Mannequin geometry with your model geometry
  6. Unparent your model geometry and Mannequin joints
  7. Export as fbx
  8. Import into UE4 choosing Mannequin skeleton as default
    That is it! Animations should work smoothly. If smth looks ugly you always can repaint weights in Maya and try again. Good luck!

Thank you!