I kept my Mangosteen seedling in good shade for a few years and then progressively brightened it over the next few years to direct sunlight. It's over 2 metres tall now.

Another I have on my place was planted by a previous owner is about 5 metres tall, don't know its age, but it's in strong filtered sunlight for most of the day.

Generally seedlings need shade for a few years at least, they're a plant that starts out life under the rainforest canopy and finally emerge through the top. Cuttings, though, could be different. I'd still keep it in shade for about a year or so before slowly bringing it into full sun. They're a beautiful plant, and an absolutely beautiful tasting fruit.