The Joy-Cons do not require a direct line of sight to the Nintendo Switch console in order to work. This means that you can still use the Joy-Cons even if there are obstacles or objects in between the console and the controllers.
I have personally used the Joy-Cons in various scenarios where there were objects blocking the line of sight, such as playing games while sitting on the couch with my legs up or even playing games from another room. The Joy-Cons have always worked without any issues.
The reason why the Joy-Cons do not require line of sight is because they use a wireless connection to communicate with the Switch console. This wireless connection is based on Bluetooth technology, which allows for a reliable and stable connection between the controllers and the console.
Bluetooth technology has been used in various devices for wireless communication, such as headphones, speakers, and other gaming controllers. It operates on a frequency band that is not easily obstructed by common household objects, so even if there are walls or furniture in between the Joy-Cons and the console, the wireless signal can still penetrate through and maintain a strong connection.
However, it is worth noting that there are some factors that can affect the performance of the Joy-Cons, even without a direct line of sight. One of these factors is distance. The farther you are from the console, the weaker the wireless signal may become, which can result in input lag or dropped inputs.
Additionally, other electronic devices in close proximity to the Joy-Cons and the console can potentially interfere with the wireless signal. This is more likely to occur in environments with a high density of electronic devices, such as crowded gaming events or areas with a lot of Wi-Fi signals. In my personal experience, I have encountered some minor interference issues in crowded gaming events, but they were rare and did not significantly impact gameplay.
The Joy-Cons do not require a direct line of sight to the Nintendo Switch console in order to work. They use a wireless connection based on Bluetooth technology, which allows for a reliable and stable connection even with obstacles or objects in between. However, factors such as distance and electronic interference can potentially affect the performance of the Joy-Cons.