Front hub motor on an X11 citycoco fat tire electric trike.

I have a 2000W Citycoco Fat Tire X11 electric tricycle. However, where I live, there are many mountains. I want to add another engine at the front to make it more powerful. Can anyone give me a tip? Is there any difference between the front and rear engines? For example, I couldn't find the front engine for sale on Aliexpress.