[2D] Move non-Kinematic Rigidbody without breaking interpolation

Hi,

I have moving rigidbody (moved with addforce in fixed update) with it's own behavior. This works correctly.
Now I want this moving object to sometime have really precises additionnal movement (added to its normal physic movement).
Exemple : to add a platform movement to the rigidbody (without adding force, not precise enough).

Here is what I tried :
- moving transform / transform.Translate : break interpolation, jerk movement. (since 5.5 even moving rotation break interpolation)
- moving rigidbody with rigidbody.MovePosition . break interpolation
- using the parenting movement (set the rigidbody child of object that do the additionnal movement) : break interpolation
- animation movement (same as transform movement).

So none of this work. Does anyone succeded to add an additional movement(even z)/rotation without breaking interpolation?

Thanks in advance