As stated the dock plugs directly into the USB-C port on the iPad and rests at the back of the device when in landscape orientation. Not only is it portable but it also works with the Smart Keyboard Cover but because of the way it rests on the device may be able to rest on the iPad Pro when using other cases.
Also, with the iPad receiving mouse support in iPadOS 13 you will be able to plug a regular USB mouse into the dock and truly have a laptop replacement. The dock is now available for pre-order today from B&H Photo and will become available later this month.
Remember, you use case may vary and the iPad may not be a good laptop replacement for you, but doing tasks like web browsing, document editing, taking notes, drawing, and photo editing are amazing on the iPad. Task like video editing are still recommended to be done on a laptop or desktop using software like Final Cut Pro X, DaVinci Resolve, or Adobe Premiere.