Foot locking can cause 'leaning'?
The auto 'foot locking' feature is good - no sliding.
I think it can create a bit of 'leaning' though.
Made this vid with avatar model, and with chroma (green screen) enabled.
Most video editing software lets you layer videos.
Got the background video, picture and music from Shutterstock (not free).
If the video was created by yourself you can try to include a perfect T-pose of yourself for a few seconds in the beginning of the video (torso straight up and arms horizontal) and see if the leaning in the result is better.
Also you can try "Foot Locking : Grounding" mode to disable to the foot locking to see if it improves the leaning.