I suppose flavor won't be changed. Most coffee beans are grown just like that. They require shade or they will die of too much sunlight. Having too much water will sometimes drown the plant to death. Here is a website that lists three main disadvantages and some advantages to shade grown coffee.
- Too much shade will cause fungal infections
If the plant is under too much shade, fungi-related infections will attack and feed on the plant. This will ruin your plant and destroy it. Yet having too much sunlight will burn the plant instead.
- The real definition of shade-grown is not really rock-solid. Many places will have varying amounts of shade due to their altitudes.
You can't say that this type of shade gown plant is used in every country of different altitudes.. Some places require more shade (those with a high altitude) and others less shade (those with a low altitude). It depends on where you will plant your coffee plant.
- The further south (or, north) a farm is located from the Equator, the less need there is for shade cover to protect coffee plants from the rays of the sun: the strength of the sun's rays in, for example, Brazil (where the sun is at an angle) is far less than the direct overhead rays from Central America. Thus, while shade cover may prove advantageous in Central America it might actually lead to a fall in yield of crops in Brazil.
This directly copied from the website, word for word. The amount of shade needed will also depends on the sunlight's strength. Nearer the equator, it is stronger so more shade is required. Farther from the equator, it is weaker so less shade is needed.
There are maybe more, but these are some basic and critical disadvantages to shad grown planting. I hope this helps you!