Blur effect

Time lapse from stills, or if your camera will let you drop you shutter speed way down.

The best result possible is by doing it in camera as u/Matterchief suggests.
For a far worse result, you can do it in post by applying a forced pixel motion blur and crank up the blur (and samples) beyond a reasonable number.
If the camera moves for even a few pixels it will ruin the effect by trowing off the pixel tracking. Camera needs to be rock solid, no drift, no wind, no shaking, etc. I suspect this is also true for the in-camera effect.
Too much pixel motion blur will generate artifacts easy to spot and the effect may simply not work for a given shot.
Try posting to r/vfx maybe someone there has a better solution.

AS u/Matterchief has already said, it's a long exposure, probably done with a DSLR as few video cameras will record a shutter exposure longer than 1 second.

So setup your DSLR with a low ISO, and an appropriate ND filter so that you can stop the shot down to a long exposure. Best results can be between 1-3 seconds depending on the kind of action that's happening. The tripod has to be rock solid.

In AE a combo of Wide Time + Echo might get you started if you must use existing footage, but just capturing an actual time lapse will be much easier and more successful. In case the posts below didn't make clear, the "video" form of these images is a long series of stills assembled like a flipbook. The amount of blur depends on the camera's shutter speed - a higher shutter speed will still give a crisp image even in a time lapse, a lower shutter speed will "smear" moving details like cars and the pedestrians in the image you linked.

Here's an example I took from my roof - something like 1500 stills put together in Final Cut.