Esthetics Porcelain Effect

Do you mean glossy, like a glazed china doll, or more a smooth semi matte of a bisque doll?

In either case, it should be possible to achieve using the right top coat, after the face up is done.
Some experimentation is probably needed to adjust the technique if you are going with full gloss, since that tends to enhance certain details and colors and may work best for simpler, more old school types of face ups. Especially if you want to mimic the style of an old porcelain doll, since they tend to have a lot less subtle detail and very little complex shading compared to most BJD face ups.

A good place to start hunting for good candidates for gloss is in the All About Sealants thread. Normally the gloss version of any matte varnish or medium that is safe for face ups, should also be fine.

 

Happy hunting! It sounds like a cool project.

 

Joy Doll did something similar with a recent sculpt, but I don't know how it was achieved. It is a cool effect!

Joy Jia Yi Chen on Instagram: "超绝的秀场妆 by @kingnut___ 看到这个妆的第一时间我就已经想好头发的质感，立马搞来材料做了这个绵羊毛假发。天然的小卷配这个脸太自然了～ （雅各布似乎被我越养越御姐了…） Jacob #bjd #bjdphotograph #doll #joydolljacob #Joydoll #bjdsalepost #sculpture #artdoll #toy #人形作家 #球体関節人形 #balljointeddoll #bjdphoto #bjdsale"