A quick search suggests this appears to be a revised version of Tanita’s MC-980 scale, which is intended for professional use and costs $13,000 USD anyway - even without King of Fighters.
So not really any difference, just a very unusual collab and bit of fun for marketing! :)
Wholesome sleeping separately because being in a relationship with someone shouldn’t obligate sacrificing your rest quality to meet the bizarre pressure of some unspoken social obligation that couples must share the same bed (unless you want to)