Differences? Not many, you probably get more differences within their individual personalities.
First generation, and recent immigrant asian women may be more reserved initially than women soaked in western culture, and may remain more deferential, but that's again possibly just the personalities involved.
The physical differences (inconsequential at best) I've noticed include breast shape, and pubic bone shape.
The asian breasts I'm familiar with have the nipple lower on the breast, with the breast shape less symmetrical top to bottom.
The pubic bone on caucasians has a cross section like a "0", and on asian women it seems tilted, more like " 0 " a italicised letter. Since this is the clitoral attach point, it can seem like everything is pushed back a bit. It all works the same, though...
I have over 15 years marriage each (consequentially) to one of each, and I don't feel it's a racist topic.
Individual personalities are by far the greater contributor to variation, though.
YMMV