Recently my 2007 Volvo XC90 3.2 AWD has started to shudder at low speeds (typically around 30 mph). I have been doing some research and I feel like the cause of this would be the torque converter. I did a stall speed test and got a 1600 rpm in drive and 1800 rpm in reverse. I am wondering if these stall speeds are low or if they are in the normal range. I am also wondering if doing a flush would fix my issues. The car currently has 229k miles. Also, I had someone hold my phone camera during the stall speed test and noticed that my engine does move back and fourth significantly when in gear. Could the shuttering be caused by my engine mounts going out?

Video of engine moving during test:
https://drive.google.com/file/d/1prC...usp=share_link