Venitian plaster holds up to bathrooms quite well.
I had it done by a local artist on a job because she was also doing murals in the house.
She took some time doing it but it was cool when she finished.
You need to prep your area good.Do any tile work first as this ties into it.
It's kind of like a rough bowling ball when it's finished.
Probably not the best analogy!!
But the last coat to go on is carnuba wax. Thats what she used anyway.
Not a painter