How to disable vibration from notifications?
You would need at least adb or root access for this to work. I'd describe the method for adb, since root access is not available or cannot be afford by just everyone. 

Once you have adb setup and working with device, issue this command:

adb shell appops set --user 0 com.ebay.mobile VIBRATE deny   


The notifications from Ebay app wouldn't vibrate your device anymore. If you want to treat other individual apps the same way, replace com.ebay.mobile with their package name. 

If you have root access or can afford some inconvenience of having to connect the device to a PC every time former is restarted, try an app like App Ops.

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