Add sequence yaw orientation and HMD orientation

Hello !

I’m fairly new to blueprints. I am currently using Unreal Engine to create and assemble audiovisual environments without complex scripts.

I made a VR project in which the viewer is transported for a journey of about 20 minutes. During the journey the spectator can only observe the environment in 360 °. Here is an export in episodes in 360 ° video :

To be transported I use a sequence which moves the fps. In the sequence the orientation (yaw) of the field of view is also defined. When reading in normal game the direction of the field of vision is oriented according to the values ​​defined in the sequence.
However, when I switch to VR mode the HMD takes precedence and the orientation of the fps is entirely set by the orientation of the head (or the mouse). However, I would like to be able to accumulate the change of orientation defined by the sequence with the orientation of the viewer’s gaze (as happens in the 360 ​​° video export of my project).

Do you have any solutions please ?

Thanks !
(and sorry for my aproximative english :))