Ok, the anwser is: multipply the parent Tranform matrix for the translation to the face direction.

For Axis studio, Z is pointing to the Avatar's front, so I only had to make the calcules.

For the moment, I don't know if works for any euler order, but solves my problem.

local_transform = np.identity(4)
local_transform[:3, 3] = np.array([0,0,10])
face_transform = parent_transform @ local_transform