2008 Ford Edge - Now it jerks

transmission jerks at steep roads ,only at low speeds,it began after I replaced the engine computer.

Could be a coincidence.
But I think your system “learns” how you use your car and adjusts the shift points, your car is still learning.
Have you routinely serviced your transmission, changed fluid every 30,000 miles? A fluid change might help.

Actually I did have the transmission taken off , opened and check all components, than put back and tested ,mechanically there’s nothing wrong , no codes etc, it did improve but like you said the change of fluid might have had some effect , the recent change of engine computer was an afterthought, thank you anyway.