Kubuntu 18.04 LTS user here. I've had similar problems. I expect what follows will apply to regular Ubuntu also.
Out of the box Ubuntu uses libinput for its touchpad control. libinput only has one setting for the pointer speed: the acceleration setting. The older Synaptics driver has minimum speed, maximum speed and acceleration.
I'm using a Huawei ...
It looks like your specific Elan touchpad (Elan 062F) can be fixed by following the steps in this thread here
The comment which fixes your problem is this
This Lenovo machine that I'd purchased also has the same issue, but with a different touchpad model.
Try these steps mentioned in the thread and let me know if it works for you.:
Disassemple the ...