Bluetooth Passthrough
This is a work in progress
Since 5.0-910, Dolphin has the ability to passthrough a Bluetooth adapter for emulated Wii software. This gives emulated Wii software full control of a Bluetooth adapter, which, provided a decent, working adapter, notably allows pairing Wiimotes to Dolphin, third-party Wiimote support, working Wiimote audio and more accurate connectivity.
Setting up
Linux
A udev rule has to be installed so Dolphin can use a Bluetooth adapter without having to get root privileges.
SUBSYSTEM=="usb", ATTRS{idVendor}=="YOURVID", ATTRS{idProduct}=="YOURPID", TAG+="uaccess"
Also, the USB Bluetooth kernel module should be unloaded, or Dolphin will not be able to use the adapter.
modprobe -r btusb # and to reload the kernel module (to restore Bluetooth): modprobe btusb
Note: it is also possible to unbind only a specific adapter from the btusb module, but for simplicity, unloading the whole module works too. Additionally, unloading can be automated by tweaking the udev rule.