One of the best things about moving to Tokyo was the change in fashion.
Where I moved from, many women had given up on appearing like women. So many resorted to pants, jeans, oversized shirts or sweatshirts... and wearing things like crocs or overly casual clothes that just made them very grey and dull.
This doesn't apply to escorts, but just women in general.
I prefer skirts, dresses and well coordinated outfits (heels, bags, makeup, tops & jewelry). Since I had never lived in a top city, I was really shocked when coming to Japan, even on my first visit here as a tourist many years ago. I know Tokyo is not the only fashionable city, but it really opened my eyes to what's really out there. I'm also a big fan of fashionable lingerie, from the simple to the overly complex. I prefer matching sets, but that's just because I've been spoiled by some of my GF's here who always had matching pieces.
I love stockings of all varieties... from the way they feel to the way they look. (in all sorts of colors and types....)
Depending on the settings -- I'd prefer a mid-length skirt (flare type, not the boring pencil skirts that have no personality) or a mini-skirt with a nice pair of legs capped by fashionable heels. (but not sky high heels that make walking awkward...) If it's a upscale dinner, then more along the lines of a formal dress... well, not wedding formal, but something black and light
To be honest, if I ever actually booked an escort and she showed up in super casual clothes... I'd be very disappointed.