Unfortunately, as of now, you cannot directly link your MagicBand to your Apple Watch. The MagicBand is a proprietary device created by Disney specifically for use in their theme parks. It is designed to be an all-in-one device that acts as your park ticket, room key, and can even store your FastPass+ selections and dining reservations.
On the other hand, the Apple Watch is a smartwatch created by Apple that offers a wide range of features beyond what the MagicBand can do. While the Apple Watch does support contactless payments through Apple Pay, it does not have the necessary technology to function as a MagicBand replacement.
That being said, there are still ways to use your Apple Watch while visiting Disney World. For example, you can use the My Disney Experience app on your Apple Watch to view wait times for attractions, make dining reservations, and access your FastPass+ selections. You can also use Apple Pay to make purchases at various locations within the parks.
Additionally, Disney has recently introduced a new feature called Disney MagicMobile, which allows guests to use their iPhone or Apple Watch to enter the parks, similar to how a MagicBand would work. This feature uses the Wallet app and allows you to add your park tickets to your device. While it is not a direct replacement for the MagicBand, it does provide a convenient way to access the parks without needing a physical ticket.
While you cannot directly link your MagicBand to your Apple Watch, you can still use your Apple Watch in various ways while visiting Disney World. From using the My Disney Experience app to making purchases with Apple Pay, there are plenty of ways to enhance your Disney experience with your Apple Watch.