I roller skate a lot (or did till pulled my groin) and coming from that perspective these things are rediculous. Heavy, loosely held to your foot, barely any thane and likely very rough anywhere but the airport, they don't let you skate in the airport unless you keep it on the dl, these are not on the dl, they look like a huge amount of complexity, engineering, and construction and probably cost.
These look like someone who didn't know how to skate might think they'd be easier but surely they're not. I don't speak French, I know they're into skating or bladding over there but in my mind these will end up in a closet. Best thing I can think for these is to take them apart and throw them on a skateboard. I forecast there will be no electric roller skate section on this site