White Swiss Shepherd / Berger Blanc Suisse
White German Shepherd
The White Swiss Shepherd (Berger Blanc Suisse), the White German Shepherd and the White Shepherd are different breeds with different standards. The White Swiss Shepherd, also known as the Berger Blanc Suisse (pronounced Berjer Blaank Swiss) is recognized by the FCI in Europe. The White German Shepherd is recognized by the AKC (although the color is disqualified for show) and the White Shepherd is recognized by the UKC. Having said that, there is a lot of overlap in the history and characteristics of all three breeds. (See: History of the White Swiss Shepherd for more information)
In general, I would place the White Swiss Shepherd and the White German Shepherd on two extremes with the White Shepherd in the middle as a transition between them and depending on the breeder, with characteristics that could resemble either.
AKC German Shepherd standard refer to the breed's strong prey drive and "fearless and direct" personality. The breed is considered an excellent police and guard dog. The White Swiss Shepherd (BBS) standard calls for a mellower, more gentle personality and the dog is not stereotypically considered for police work or guard dog work but, instead does well as a therapy or service dog. The personality of a White Shepherd represented by AWSA might reflect either, and is likely dependent on the breeder's standards and goals for their breeding program.
In terms of physical characteristics, the biggest difference between the White Swiss Shepherd (BBS) would be the hip angulation. The White Swiss Shepherd standard calls for a more upright stance, whereas the White German Shepherd standard would follow AKC's German Shepherd standard for a more severe angulation.