For Dell cheap low end black plastic cover model, such as Inspiron 15" 3567 i3 cpu, please install the touchpad driver form Dell's product site.
eg. Dell-Touchpad-Driver_YYK15_WIN_19.2.17.64_A10_02_180515

It is Symantec device driver. Mice and other pointing devices will show as "Dell Tochpad" under Device Manager. Automatic Windows update will not download the right driver to enable two finger gesture function. 

Installation setps:
1. Fresh install Windows 10
2. Install latest service pack (knowledge base)
3. Install Touch Pad driver
4. Install SDI. Do not install any Touch Pad releated drivers, it may cause issues.
Note: Sometime you can't just uninstalled the TP driver and install the new one to make two-finger gesture function to work. 

For Dell cheap low end black plastic cover model, such as Inspiron 15" Pentium cpu, please install the touchpad driver form Dell's product site. The file name is Intel SerialIO.

For newer or more expensive models, such as G3 or sliver cover AMD Ryzen, Mice and other pointing devices will show "HID-complaint mouse".