Well, maybe not mainstream society "fashionable", but the Kodona, Prince, or Boystyle fashion is just about as popular as the Japanese Lolita, & Japanese Gothic styles. Although most popular in Japan & a few other Asian areas, you will see people going out to an event or party in almost any large city in the world wearing that stuff... not just on Halloween.
I haven't seen anybody going out in my town in Kodona or Lolita styles, but they have been sighted in neaby Toronto, & in NY city. You can see people wearing real sissy outfits occasionally there too. I have read about people in my area wearing Kodona & Lolita stuff at home, but much like most sissy & ABDL outfit wearers, they're not going out to an event in them.
Of course I suspect people who like these are probably fans of sissy outfits too. They can wear these styles with less criticism, because they're considered costumes, & offshoots of the cosplay fan base rather than a real sissy outfit.
You can still go to some wedding shops & get a paige boy outfit with a peter pan collar or frilly top with short pants, or bloomer-like pants too. Some of the pix of paige boy outfits here are pix of current stock at some wedding & formal wear shops.
Just like the modern "brolita" (boy lolita) & lolita fashions, it demonstrates there will always be a small portion of society that will always appreciate frillier fashions, & as long as they exist, someone will produce them for those people.
Look at how many sissy & ABDL shops there are online. Lolita, Brolita, Kodona, Boystyle, & Prince are a cheaper alternative, without admitting any sissy feelings or fetishes about it.
It's like most of the cars on the road today are silver, silver grey, black, or white. Blue cars are a minority, but there will always be some people who want a blue car, so although they don't make as many of them, they do produce some blue cars for those who like blue.
Long hair on men may not be fashionable anymore, but if you walk through any town, or turn on the TV, you'll see some men & boys still wearing long hair. It may not be fashionable for mainstream society, but fashionable to a minority.
My hair hangs down all the way down to my nipples. I don't get any criticism about it or get any strange looks. Everybody treats me just like a regular guy. Of course in my town, my face is well known from being in the entertainment industry in the past. I've looked the same for decades. Even if somebody doesn't know me, there's a good chance they've seen me around several times before. So my long hair is practically my trademark. It's how people have always seen & known me. Been wearing my hair long for 45 years.
Interestingly, at a time during & just after the hippie era, when men & boys in long hair was fashionable, is when I got the most criticism about it. Down in the southern states in those days, gangs used to beat up men with long hair, & then forcibly cut their hair. Those same redneck areas are where men with long hair are the most common today. Those rednecks always seem to be 40-50 years behind everybody else.
Now that it's not fashionable anymore, nobody cares about my hair... except a few people threatened to kill me if I ever cut my hair.