Any advice to prevent vertical jitter in animation?

Dear all,
I am working on the good settings for rendering this animation, show a part of it here.
In the movement of the objects a jitter appears, specially at the clavicles.
I tried to adjust the settings, but it did not solve anything.
First I rendered the sequence with quite default settings. Then I changed it in the render settings to;
Render settings;
GPU compute,
500 samples,
denoising NLM,
Seed 0 clock on, (instead of clock unchecked)
Pattern Progressive Multi-Jitter (instead of Sobol)
Pixel Filter Blackman-Harris width 1.6 px (instead of 1.5px)

I rendered PNG with an Alpha, transparent background 16 bits (instead of 8 bits)

All these extra settings do not give a big difference

I wonder if it is worth to do a next test without the Alpha, since maybe it has something to do with the transparency overlap, when doing the editing in the video?

Do I oversee something?