Hello,
From the photos, it seems to me common E.pyrifomis, I needed a photo of the whole plant, I never saw uvaia cultivated in the shade, always in full sun, even in the forest, they get huge disputing sun with other trees.
99 percent of the Uvaia are sour, they vary a lot, on the shape and the flavor generally, it is good but sour, it reminds me of the taste of Eugenia Spitata (Araca Boi), There is a hybrid of E Pyriformis x E Lutecens, which is sweet , but nothing like some guys talk about sweet as honey, is acidic.
All these fruits have a characteristic of rapid fermentation, do not serve to store their pulp, or make juices to consume many hours later, and as soon as you remove the fruit from the tree it becomes soft, almost liquified.
You can make juices, jellies and ice creams, once a Taiwanese asked me for 2,000 Uvaia seeds, to plant and sell the fruit in the supermarket, like a fresh fruit, I made a video at the time explaining about this fermentation characteristics and he gave up this huge amount.
It is a fruit very attacked by the fruit fly.
I really like this tree, it's a wild tree where I live, and every place it varies a lot, in the shape of the fruit and in the flavor.
Aexandre